Sports Exercise Science – Page 18

Professional Team Physicians Beware! Co-employee Status May Not Ipso Facto Confer Tort Immunity

Submitted by: Timothy J. Paterick, Barbara B. Paterick, JD & Timothy E. Paterick, MD, JD

Abstract:

The relationship between a professional athlete, his or her professional sports team, and a team physician is legally complex and has inherent potential for conflict. Although a physician should always consider an athlete’s best interest when determining an athlete’s fitness to participate in competitive sport, a physician also has a responsibility to his or her employer to act in the best interest of the team. The dual role of a team physician results in the potential for conflict if a professional sports team and the professional athlete’s best interests do not coincide. The workers’ compensation co-employee doctrine immunizes a professional sports team from vicarious liability in tort for its team physician’s negligence. Recent judicial opinions and legal commentary suggest that the workers’ compensation law barring tort suits between a professional athlete and a co-employee team physician for injuries caused within the scope of employment should not ipso facto confer absolute tort immunity for a physician. The argument being made is that if a team physician breaches the ethical and legal duty to provide the standard of care, the co-employee doctrine should not provide a shield from tort liability for harm caused to professional athletes. Physicians must be aware of legal opinions surfacing in the literature so they can understand that their most prudent approach, no matter what the circumstance, is to practice in a manner in which a professional athlete’s health interest supersedes all other interests.

Introduction:

Present-day judicial opinions and legal commentary suggest that the absolute tort immunity provided under the co-employee doctrine of workers’ compensation law may need limits to encourage the implementation of medical care that, above all other interests, protects the health and safety of professional athletes. Sport- medicine physicians involved as co-employees in the care of professional athletes must be aware of current opinions and commentary to better understand their risk of liability. The shield of workers’ compensation law may not be a fail-safe defense for employed team physicians. Judicial and legal commentary about tort immunity in the context of the co-employee professional sports physician demonstrates why a prudent approach by all professional team physicians, despite their co-employee status, would be to act as a fiduciary where an athlete’s health interest supersedes all other interests.

The Team Physician and the Professional Athlete

The most frequent claim raised against a team physician by a professional athlete is negligence. Negligence for sports medicine physicians may arise for 1) allegedly failing to diagnose a medical condition in an athlete, 2) failing to appropriately warn an athlete of a medical condition when the condition is diagnosed, or 3) improperly deeming an athlete medically safe for sports competition when a physician knows or should know of an imposing medical condition that should limit or suspend competition.

To establish a negligence claim, an athlete must prove four elements: first, that a duty of care exists between the athlete and the team physician; second, that the team physician has breached that duty; third, that the breach caused harm to the athlete; fourth, that the athlete has sustained injuries that can be quantified into damages.

Physician Duty

The existence of a patient-physician relationship legally establishes a physician’s duty to appropriately diagnose and treat patients. In the environment of sports medicine, this relationship also involves a duty to disclose any material information to an athlete about his or her physical condition and to sufficiently inform an athlete regarding potential risks of participating in the sport. This is, arguably, a variation on the doctrine of informed consent; that is, an athlete must have all available information to make an informed decision to participate in a sport. Team management should expect a sport-medicine physician to discuss with management and athletes the risks and benefits of playing a sport on the basis of a medical evaluation.

Breach

Demonstration of a breach of the duty of care requires establishment of the appropriate standard of care. A team physician should consider only an athlete’s best interest when determining an athlete’s fitness to participate in competitive sports. A physician’s determination should be based on a broad range of variables, including 1) the physical demands and intensity of the sport in relation to an athlete’s unique clinical condition; 2) whether an athlete has previously participated in a sport with similar physical demands; 3) all available clinical, personal, and family history and a comprehensive physical examination of an athlete; 4) available medical organization and national conference guidelines pertinent to participation in competitive sports; 5) the probability and potential severity of adverse health events from sports participation, given an athlete’s unique health status; 6) whether medication, monitoring, or protective equipment could mitigate the potential health risks and support safe sports participation; and 7) in the case of minors and young adults, whether an athlete has the capacity to make an informed decision if risks are present (Krueger v. San Francisco Forty Niners, 1987).

The standard of care has evolved as sports medicine has evolved from general medical practice to specialty practice. Supportive of the theory that sports medicine involves specialized practice and a potentially higher standard of care is the publication of guidelines by medical societies and specialty boards which have articulated medical clearance guidelines for use by clinicians making athletic participation recommendations (Maron et al., 1996). Courts have recognized standards and guidelines by national medical associations as evidence of acceptable medical practice (James v. Woolley, 1988).

Expert medical testimony is necessary to establish a breach of the standard of care. For example, an expert may testify that any treatment that benefits the short-term needs of a team but creates long-term damage to a competitive athlete is a breach of duty to an athlete (Keim, 1999).

Causation

The burden of proof that the breach caused injury or harm is an athlete’s. A physician’s failure to recognize or failure to warn of potential harm must result in injury to an athlete. Causation requires a nexus between a physician’s negligence and the actual damage an athlete has sustained.

Causation may be reviewed at two levels: 1) cause in fact and 2) proximate cause. Cause in fact occurs when a physician’s action is a cause of the actual harm to an athlete. Proximate cause considers whether a physician’s behavior is a substantial factor in causing the harm an athlete may have incurred as a result of a physician’s actions or inactions. For example, an argument can be made that a physician’s failure to identify risk factors for heat stroke was the proximate cause of an athlete’s death (Lapchick, 2006). Alternatively, failure to disclose the extent of an existing injury could be considered the proximate cause of a further injury (Krueger v. San Francisco Forty Niners, 1987).

Damages

Damages may include long-term recovery from an injury and loss of salary or limitations to other work capacity because of inability to play after injury. In the case of an athlete’s death, the claims are typically pursued by an athlete’s estate or surviving kin. It is their responsibility to prove what an athlete’s life may have been worth in order for a court or jury to award damages. Awarding damages is an attempt to make an athlete whole, that is, as though the injury never occurred. Expert medical testimonies, in conjunction with an economic analysis provided by an expert economist, are often necessary to measure damages.

Although negligence is the most frequent claim brought against team physicians, other claims have been successfully and unsuccessfully litigated, including, but not limited to, 1) fraudulent misrepresentation, 2) concealment of medical information, 3) intentional infliction of emotional distress, and 4) when an athlete is not cleared to play, discrimination under the Americans With Disabilities Act (1990) and the Rehabilitation Act (1973). Each of these claims deserves to be evaluated as a unique legal concept, and they are not discussed here.

Is the Shield of Workers’ Compensation Law a Myth for a Physician Employed by a Professional Sports Team?

Interaction of Workers’ Compensation and Tort Law

Workers’ compensation law is state defined. Thus, it varies by jurisdiction. Generally, in the case of an employee injured while acting within the scope of employment, workers’ compensation law is thought to be an efficient and adequate remedy to compensate injured employees without the necessity of proving fault of an employer. The law allows compensation for employees for work-related injuries. In exchange for the absolute requirement to pay injured employees, the law shields employers by setting recovery limits at modest amounts and specifying the remedy provided as the exclusive remedy (Workers’ Compensation Law, 1993). No tort liability is allowed.

A professional athlete is entitled to workers’ compensation benefits for aggravation of an athletic injury caused by the negligent care by a team’s medical personnel. A player whose injury is secondary to negligent medical care or the failure to provide reasonable medical care is barred from recovering tort damages against the team or its employees, including a team physician who has co-employee status (Keim, 1999; Mitten, 2002).

Generally, the exclusivity provided under workers’ compensation law bars all tort claims against physicians employed by professional sports teams. It is likely the defense on which most employed team physicians rely when sued for negligence by an employed athlete.

There is an exception in most jurisdictions for certain common law claims, such as injuries resulting from the fraud or defamation of an athlete by a team physician, team management, or both. Similarly, the exclusivity remedy provisions of the state workers’ compensation laws will not bar a medical malpractice claim against an employer or co-employee team physician for an injury caused by conduct intended to harm an athlete (Hertz, 2001; Mitten, 2002).

Beyond the exceptions carved out for fraudulent and intentional tort claims, some courts’ dissenting opinions, as well as some legal commentaries, argue for the erosion of the shield of workers’ compensation as a fail-safe defense for employed team physicians. One argument is that a special relationship exists between a team physician and a professional athlete, extending the duty of care beyond the duty of a company physician to a company employee. The argument is grounded in the belief that professional sports have elevated economic incentives, and the pressure to win causes a team physician to meet the teams’ immediate needs rather than the health interests of professional athletes. The belief is that potential tort liability creates a legal incentive which urges team physicians not to succumb to the pressures that are inherent in professional sports.

Korey Stringer, a professional football player for the Minnesota Vikings, died from complications of heat stroke during preseason training camp in 2001. His heirs alleged that the Vikings’ team physician provided negligent medical care. In Stringer v. Minnesota Vikings Football Club, LLC (2004), the trial court held that there is no immunity if a co-employee, in this case the team physician, owes a personal duty of care to a fellow employee, namely the football player, which is “not pursuant to the employer’s non-delegable duty to provide a safe workplace.” Thus, the trial court is saying that the employer has a duty to provide a safe workplace for all employees, and beyond that, team physicians have a separate duty of care to football players that goes beyond the owner’s responsibility to provide a safe workplace. Reversing the decision, the Minnesota Supreme Court (Stringer v. Minnesota Vikings Football Club, LLC 2005) subsequently ruled that the Minnesota Vikings team physician’s duty to the professional athlete was fulfilled within the employment relationship and the professional sports team’s effort to provide a safe workplace for its players. Thus, the Minnesota Supreme Court ruled that, in the case of Korey Stringer’s death, the team physician did not have a separate duty of care to the football player beyond that of the team owner to provide a safe workplace. The dissenting opinion for the Minnesota Supreme Court expressed doubt that concealing the duty of a co-employee physician under the umbrella of an owner’s responsibility to provide a safe workplace is a reliable legal remedy when a physician co-employee provides medical care to employees. The dissent also articulated a policy argument stating that extending immunity to co-employee physicians would encourage them to neglect their duties. Of note, dissenting opinions do not define the law but can give authority to an argument supporting a change in the law.

The California case of Hendy v. Losse (1990) raised issues that make the absolute immunity of a co-employee team physician less certain. Hendy explored a dual-capacity theory, that is, when an employer has two separate relationships with employees. An employer, normally shielded from tort liability by the exclusive remedy principle, may become liable in tort to an employee if the employer occupies, in addition to its capacity as employer, a second capacity that confers additional obligations. California courts have long recognized that a physician, as an employee of a company, may operate in the dual capacity of co-employee and physician. In Hendy, a professional football player’s malpractice case against the team physician was allowed to proceed at the trial level on the basis of the dual-capacity doctrine. The California Supreme Court (1991) dismissed the claims, holding that the state’s workers’ compensation laws bar tort suits between co-employees for injuries caused within the scope of employment. However, the Supreme Court stated that if a co-employee provides medical care other than that contemplated by the employee’s employment, the physician co-employee no longer enjoys immunity from tort.

Some legal commentators have articulated the belief that if a team physician breaches his or her duty of care to a team’s athletes, the co-employee doctrine should not provide a shield from tort liability. According to Young (2003), “[A]ny notion that a doctor’s co-employee status will shield his liability to a patient he negligently treats should … be removed.” In Mitten’s opinion (2005), “[A] team physician should not have immunity from malpractice merely because he or she is characterized as an ’employee.'”

Conclusions:

Professional sport-teams physicians in charge of clearing professional athletes for competition and treating professional athletes’ injuries have a complex position with unique responsibilities to athletes. A co-employee professional team physician should be mindful of the best interests of athletes and sustain the appropriate standard of care. If physician negligence is alleged, workers’ compensation laws may shield a physician from tort liability arising from injuries occurring in the course of an athlete’s employment, so long as there is no finding of fraudulent or intentional misconduct. However, the dual-capacity doctrine articulated in Hendy, the dissenting opinion from the Minnesota Supreme Court in the Korey Stringer case, and expert legal commentary should give physicians, acting in the co-employee role for professional sports teams, reason to reflect on their potential liability. A prudent approach-in an attempt to reduce potential for tort liability-would be to understand that, despite the co-employee status of team physicians, all the inherent responsibilities of independent contractor physicians, who are not shielded from tort liability, may apply in a court of law, and an athlete’s medical interest should supersede all competing interests.

References:

Americans with Disabilities Act, 42 USC §§1210 et seq; 1990.

California Supreme Court 819 P.2d 1 (Cal. 1991).

Hendy v. Losse, No. D010557. Court of Appeals of California, 4th appellate District, Division One. 231 Cal. App. 3d 1149; 274 Cal. Rptr. 31; 1990.

Hertz, G. (2001). Professional athletes and the law of workers’ compensation: rights and remedies. Law of Professional and Amateur Sports, 2, 15-1.

James v. Woolley. 523 So. 2d 110, 112 (Ala. 1988).

Keim, T. (1999). Physicians for professional sports teams: Health care under pressure of economics and commercial interests. Seton Hall Journal of Sport Law, 9, 139-58.

Krueger v. San Francisco Forty Niners. 189 Cal. App. 3d 823, 2 Cal. Rptr. 579 (1987).

Lapchick, R. E. Dying for the game. Retrieved June 9, 2006, from http://www.northeastern.edu/csss/rel-article22.html.

Maron, B. J., Thompson, P. D., Puffer, J. C., McGrew, C. A., Strong, W. B., Douglas, P. S., et al. (1996). Cardiovascular preparticipation screening of competitive athletes: A statement for health professionals from the Sudden Death Committee (clinical cardiology) and Congenital Cardiac Defects Committee (cardiovascular disease in the young), American Heart Association. Circulation, 94, 850-856.

Mitten, M. J. (2002). Emerging legal issues: A synthesis, summary, and analysis. St John’s Law Rev, 76, 5.

Mitten, M. J. (2005). Team physicians as co-employees: A prescription that deprives professional athletes of an adequate remedy for sports medicine malpractice. St. Louis Univ Law J, 50.

Rehabilitation Act, 29 USC §§504, 794; 1973.

Stringer v. Minnesota Vikings Football Club, LLC. 686 N.W. 2d 545 (Minn. App. 2004).

Stringer v. Minnesota Vikings Football Club, LLC. 705 N.W. 2d 746, 762 (Minn. 2005).

Workers’ Compensation Law 68.13 (1993).

Young, J. D. (2003). Liability for team physician malpractice: A new burden shifting approach. Rutgers L Rec, 27:4.

U.S. Sports Academy2016-10-12T14:53:11-05:00March 14th, 2008|Sports Coaching, Sports Exercise Science, Sports Facilities, Sports Management|Comments Off

The Comparison of Maximal Oxygen Consumption Between Seated and Standing Leg Cycle Ergometry: A Practical Analysis

Submitted by: A. Bosak, J. Green, T. Crews & R. Deere

Abstract:

Because previous studies have been equivocal, the current study compared VO₂max between seated and standing cycle ergometry protocols in male (n=14) and female (n=22) volunteers of average cardiovascular fitness. All subjects completed maximal exertion seated (SIT) and standing (STD) cycle ergometry GXT protocols at 60 rev/min (rpm), with resistance increased by 30 Watts/min. SIT required individuals to remain seated for the duration of the test until achieving volitional exhaustion. For STD, subjects performed seated cycling until they felt it was necessary to stand to continue the GXT. Subjects were then required to stand and perform “standing cycling” (resistance increased 30 Watts/min) to volitional exhaustion. VO₂max (ml/kg/min), peak HR (b/min), peak RER, and peak V_E (L/min) were compared between SIT and STD using MANOVA. Results were considered significant at p ≤ 0.05. VO₂max_STD (37.9 ± 8.0) was significantly greater than VO₂max_SIT (36.8 ± 6.6), while HR_STD (190 ± 9.5) was significantly greater than HR_SIT (187 ± 9.6). VO₂max_STD was, on average 2.0% greater than VO₂max_SIT, with a range of -16.9 to +17.4%, while HR_STD was, on average 1.2% greater than HR_SIT, with values ranging from -5.6 to +7.4%. VE_STD (86.0 ± 31.6) was not significantly different than VE_SIT (82.6 ± 26.8), while RER_STD (1.21 ± 0.096) was significantly lower than RER_SIT (1.23 ± 0.065). Results suggest that the utilization of a standing protocol should be considered when cycle ergometry is the selected testing mode. Future research should seek to determine the characteristics of subjects who do/do not benefit from a standing cycle ergometry protocol.

Introduction:

Maximum oxygen consumption (VO₂max) represents the highest rate at which oxygen can be consumed and utilized to produce energy sustaining aerobic activity. VO₂max is regarded as the gold standard for assessing aerobic fitness. It is acknowledged as a substantial backbone for prescribing appropriate exercise and training intensities. Therefore, accurate determination of VO₂max is vital.

Throughout history, VO₂max has been assessed during numerous exercise modes such as treadmill, rowing, and cycle ergometry. Different modes and protocols have been compared to determine which protocol and/or mode permits the highest VO₂max (Beasley, Fernhall, and Plowman, 1989; Coast, Cox, and Welch, 1986; Faria, Dix, and Frazer, 1978; Lavoie, Mahoney, and Marmelic, 1978; McArdle, Katch, and Katch, 2006; Mckay and Banister, 1976; Moffat and Sparling, 1985; Pivarnik, Mountain, Graves, and Pollock, 1988; Ricci and Leger, 1983; and Welbergen and Clijsen, 1990). Compared to seated cycle ergometry, treadmill exercise usually permits a higher VO₂max due to the activation of more muscle mass and less pronounced leg fatigue. One of the more common VO₂max tests implemented in exercise physiology labs is the Bruce treadmill protocol (Beasley et al., 1989; Fernhall and Kohrt, 1990; Kelly et al., 1980; Lavoie et al., 1978; Marsh and Martin, 1993; Moffat and Sparling, 1985; Ryschon and Stray-Gunderson, 1991; Verstappen, Huppertz, and Snoeckx, 1982; and Welbergen and Clijsen, 1990). Despite greater VO₂max values obtained during treadmill exercise, cycle ergometry has many advantages, including preference of subjects to use the cycle ergometer during a VO₂max test, adaptability, safety, ease of calibration, and subjects’ tolerance of non-weight-bearing exercise (Mckay and Banister, 1976; Pivarnik et al., 1988). Therefore, exercise scientists have continued to explore ways to manipulate cycle ergometry protocols to allow subjects to attain the highest possible “cycling” VO₂max values (Faria et al., 1978; Heil, Derrick, and Whittlesey, 1997; Kelly et al., 1980; Lavoie et al., 1978; McKay and Banister, 1976; Moffat and Sparling, 1985; Nakadomo et al., 1987; Tanaka and Maeda, 1984; and Tanaka, Nakadomo, and Moritani, 1987).

Montgomery et al. (1971) concluded, for five male subjects, that VO₂max during standing cycle ergometry (57.35 ml/kg/min) was not significantly different than seated cycle ergometry (49.30 ml/kg/min). Tanaka et al. (1996) also found no significant differences between seated (66.4 ± 1.6 ml/kg/min) and standing (66.4 ± 1.7 ml/kg/min) VO₂max during level cycle ergometry for seven competitive male cyclists. Conversely, in a sub-study, Tanaka et al. (1996) found, for seven male subjects cycling at a 4% incline, a greater VO₂max (2.82%) for standing (56.8 ± 0.9 ml/kg/min) vs. seated (55.2 ± 0.9 ml/kg/min) cycle ergometry. Also, Ryschon and Stray-Gundersen (1991) concluded, with 10 cyclists (eight males and two females), that standing submax VO2 values were 10.8% higher than seated values during 4% incline standing cycling. Kelly et al. (1980) determined, for 12 male university students, that standing (57.91 ± 5.74 ml/kg/min) during a cycle ergometry VO₂max test produced a significantly greater (4.4%) VO₂max compared to the seated position (55.12 ± 6.98 ml/kg/min). Also, Nakadomo et al. (1986) concluded that, in 22 male subjects, VO₂max was 17% higher while standing as compared to the seated position. Support of level standing cycling ergometry eliciting higher VO₂max values continued when Tanaka et al. (1987) showed that 14 well-trained runners, 8 rowers, and 6 males of average fit attained higher VO₂max values when standing as compared to seated cycle ergometry.

Fitness level, as well as the type of athlete and gender, can affect VO₂max values (Basset and Howely, 2000; and Foss and Keteyian, 1998). For example, trained cyclists achieve higher VO₂max values during cycle ergometry compared to sedentary individuals and trained runners (Tanaka et al., 1996). This trained versus untrained comparison supports the notion that athletes who train in a certain mode of exercise can attain a higher VO₂max in that specific mode (Fernhall and Kohrt, 1990; Ricci and Leger, 1983; Tanaka et al., 1996; and Verstappen et al., 1982). Also, males tend to have higher VO₂max values than females due to greater lung capacity and greater amounts of hemoglobin (Foss and Keteyian, 1998). Subjects in previous studies varied in terms of fitness level and preferred mode of exercise, which may have influenced results.

Another important component of cycle ergometry protocols is the revolutions per minute (rpm). As noted earlier, leg fatigue, particularly in the upper thigh, may cause an individual to finish a cycling GXT prematurely (McKay and Banister, 1976). Lower rpm tend to increase leg fatigue (Beasley et al., 1989). Typically, for untrained individuals, 40-60 rpm provide the most economical cadences, yet 80-120 rpm yield the greatest VO₂max and lowest perceived leg fatigue at similar workloads (Beasley et al., 1989; and Marsh and Martin, 1993). Cyclists prefer to cycle at 90 rpm (Marsh and Martin, 1993). However, disparity does exist between the optimal cadences for trained and untrained individuals. Beasley et al. (1989) and Pivarnik et al. (1988) showed there were no differences in VO₂max and peak HR at 50 rpm and 90 rpm with trained male subjects, while Coast, Cox, and Welch (1986) showed the most economic range of rpm for this group was 60-80. Swain et al (1992) determined that VO₂max and HR were actually lower at higher (84) rpm vs lower (41) rpm. Hagan, Weis, and Raven (1992) concluded that, at higher rpm, (90 rpm vs 60 rpm) HR, V_E, and cardiac output will be greater, while cycling economy decreases. In contrast to the results of Hagan et al. (1992), Nickleberry and Berry (1996) determined that recreational cyclists were able to increase their time to exhaustion by 6 minutes, while competitive cyclists continued for 8 minutes longer at 80 versus 50 rpm.

In examining standing cycle ergometry, it may be prudent to recruit a more homogeneous group with respect to fitness and with representatives of both genders being tested. This process may improve validity in comparisons of standing and seated VO₂max values, which can be applied to a larger population. Based on previous results, it is unclear whether standing VO₂max values will be greater than seated VO₂max values. In previous research, all standing cycling protocols varied in terms of when to stand during trials, duration of standing, protocol duration, cadence, fitness levels of subjects, and number of subjects. The differences among procedures and methodology may partially explain the contradictory results. Since equivocal results have occurred regarding standing cycle ergometry, the purpose of this study was to compare VO₂max between standing and seated cycle ergometry protocols in female and male subjects.

Methodology:

Subjects included 14 males and 22 females. All were apparently-healthy volunteers from 18-28 years of age. Subjects were of average fitness abilities. All subjects were made aware of the risks and requirements of participating in the study and all signed a written informed consent prior to any testing. To ensure the safety of the subjects, individuals were required to complete a physical-activity readiness questionnaire (PAR-Q) and a health status questionnaire prior to data collection.

Subjects were tested on a model 824E Monark Cycle Ergometer. Each subject wore a Hans Rudolph facemask with expired gas being collected and VO₂ being analyzed by a Sensormedics 2900 Metabolic Measurement System. Individuals also wore a Polar Heart Rate Monitor (Model Polar Beat HRM) to determine exercise heart rate. Body-fat percentage was determined using Lange skinfold calipers with a 3-site skinfold method. Weight and height were measured using a detecto balance type scale with an attached measuring rod.

Descriptive data was collected immediately prior to the initial VO₂max test.
After subjects reported to the lab, an explanation of the study was provided and the initial screening procedures were administered. Instructions regarding the exercise trial were also provided to the subjects. Subjects were then assessed for height, body weight, and body-fat percentage using a 3-site skinfold technique (Pollock, Schmidt, and Jackson, 1980).

Subjects underwent two VO₂max tests (SIT and STD) on a cycle ergometer. Because subjects were of average fitness, cadence was set at 60 rpm for the duration of the tests (Beasley et al., 1989; and Marsh and Martin, 1993). Initially, subjects warmed up at a resistance of 30 watts for four minutes at 60 rpm. Every minute thereafter, resistance was increased by 30 watts until the subjects reached volitional exhaustion. SIT required each individual to stay seated until the test was terminated (at volitional exhaustion), while STD required individuals to stand at the point at which they felt they could no longer continue in a seated position. They continued to perform “standing cycling” to volitional exhaustion. All tests were stopped when subjects reached volitional exhaustion or when testers felt it was not safe for the subjects to continue. At the completion of each VO₂max test, subjects were monitored during a low intensity cool-down. SIT and STD lasted approximately 7 to 15 minutes and were completed in a counterbalanced order on two separate days with three to seven days between each session.

Expiratory gas was analyzed using a Sensormedics 2900 Metabolic cart, which was calibrated prior to each test using a three-liter syringe and gases of known concentration. The system provided updates of metabolic data (VO2, VO_E, RER) every 20 seconds. Also, a Polar Heart Rate monitor was used to monitor heart rate response (HR) every 60 seconds. Heart rate, VO₂max, RER, and VO_E were compared between SIT and STD. The highest observed values for metabolic data were considered “max” values for each respective cycle ergometry trial. The criteria for achieving a “true” VO₂max were a) failure of HR to increase with further increases in exercise intensity, b) RER exceeded +1.15, and c) a rating of perceived exertion (RPE) of more than 17 (Balady et al., 2000). In the present study, meeting two out of the three criteria satisfied the requirement for achieving a “true” VO₂max. VO₂max, HR, RER, and VO_E were analyzed using a multivariate repeated measures analysis of variance (MANOVA). Mean time to exhaustion for STD and SIT were compared using a paired t-test. Results were considered significant at p ≤ 0.05.

Results:

Descriptive characteristics of all subjects are displayed in Table 1. Physiological responses to seated and standing cycle ergometry are presented in Table 2. Percent increases of standing cycle ergometry are found in Table 3. The results suggest that VO₂max_STD was significantly greater than VO₂max_SIT with a mean difference of 1.1 ml/kg/min. Also, HR_STD was significantly greater than HR_SIT with a mean difference of 2.4 b/min. For VO_E, VE_STD was not significantly different (p = 0.08) than VE_SIT. However, RER_SIT was significantly greater than RER_STD.

Regarding mean time to exhaustion, subjects cycled 10:15 ± 2:21 minutes during SIT, with individuals cycling between 7-15 minutes. Although the difference only approached significance (p = 0.064), subjects were able to cycle on average 11 seconds longer (10:26 ± 2:06 minutes) during STD, with participants cycling between 7:20, and 15:20. When subjects were in the standing position, the mean duration of standing cycle ergometry time to volitional exhaustion was 50.42 ± 15.57 seconds.

Table 1: Descriptive Characteristics of Subjects (n=36)-Values are means and standard deviations.

	Males (n=14)	Females (n=22)	All Subjects
Age (years)	23.07 ± 2.97	19.73 ± 1.20	21.03 ± 2.63
Height (inches)	70.93 ± 3.17	65.59 ± 2.11	67.67 ± 3.66
Weight (lbs)	190.14 ± 23.36	139.00 ± 15.79	158.89 ± 31.49
Body Fat (%)	10.90 ± 4.45	21.41 ± 4.20	17.33 ± 6.71

Table 2: Physiological Responses during SIT and STD-Values are means and standard deviations. * Significantly different (p ≤ 0.05) (STD versus SIT)

	VO₂max (ml/kg/min)	HR (b/min)	VO_E (L/min)	RER
SIT	36.82 ± 6.63	187.3 ± 9.6	82.64 ± 26.77	1.23 ± 0.065
STD	37.93 ± 8.01*	189.7 ± 9.5*	86.02 ± 31.64	1.21 ± 0.096*

Table 3: Percent Increases for Standing Cycle Ergometry

	Mean Percent Increase	Range of Percent Increase	Standard Deviation
VO₂max	2.0%	-16.9% to +13.7%	+ 6.6%
HR	1.2%	-5.6% to +7.4%	+ 2.9%
VO_E	0.8%	-38.1% to +41.7%	+ 17.5%
RER	-2.3%	-16.4% to +13.6%	+ 6.6%

Discussion:

Finding ways to achieve the highest cycling VO₂max has important implications in exercise prescription, fitness evaluation, and cycling performance and training. Therefore, the results of the current study examined whether standing cycling VO₂max values are significantly greater than seated VO₂max values, which might support the use of a standing cycle ergometer protocol for all cycle ergometry Graded Exercise Tests (GXT) in exercise science and sport-performance laboratories. The use of such a protocol may generate the highest cycle ergometry VO₂max values. In terms of gender, prior research has tested only male subjects. Therefore, it was of practical importance to administer the standing and seated cycle ergometry protocol to female subjects in the current study.

Previous results regarding standing cycle ergometry have been equivocal. Kelly et al. (1980), Nakadomo et al. (1987), and Tanaka et al. (1987) showed significantly greater standing VO₂max, while Montgomery et al. (1971), and Tanaka et al. (1996) showed no significant differences in seated and standing VO₂max. Similar to the results of Kelly et al. (1980), Tanaka et al. (1987), and Nakadomo et al. (1987), as well as Tanaka et al. (1996), the current results suggest that VO₂max_STD and HR_STD are significantly greater than VO₂max_SIT and HR_SIT (Table 2).

The current study showed a significantly greater (2.0%) VO₂max and a significantly greater (1.2%) HR during STD compared to SIT. The greater VO₂max and HR during STD can be explained by a variety of reasons. Based on previous research, it is likely that with greater force production, a larger amount of muscle mass was involved during STD (McLester, Green, and Chouinard, 2004; Nordeen-Strider, 1977). Also, standing during STD may have activated more muscle mass, as the legs supported the individual’s body weight as opposed to being supported by the saddle during SIT (Nakadomo et al., 1987; Ryschon and Stray-Gundersen, 1991; and Tanaka et al., 1987). Also, as noted by Ryschon and Stray-Gundersen (1991), and Tanaka et al. (1987), during standing cycle ergometry, the upper body is involved to a greater degree in torso stabilization and purposeful side-side rocking, compared to seated cycling. Kelly et al. (1980) and Ryschon and Stray-Gundersen (1991) suggested the standing cycle ergometry protocol provides more extensive involvement of the arm and leg muscles, eliciting greater blood flow and higher work output and contributing to a higher peak HR and VO₂max, which may have also contributed to the findings of the current study.

Tanaka et al. (1987) suggested that decreases in subject cycling economy and attenuated leg fatigue might also explain the greater VO₂max_STD and HR_STD. Ryschon and Stray-Gundersen (1991) note that greater cardiorespiratory and metabolic requirements of the standing position decreases the efficiency of the rider, yet provides an increase in the total work output. For leg fatigue, subjects in the current study often verbally reported feelings of intense local discomfort and fatigue in the region of the quadriceps muscle when in the seated position and near or at volitional exhaustion. This leg fatigue and discomfort, coupled with gradual increases in resistance, may have limited the ability of the subject to continue cycling in the seated position (Nakadomo et al., 1987; Tanaka and Maeda, 1984; and Tanaka et al., 1987). However, many subjects verbally reported that at the onset of standing cycling, leg fatigue and local discomfort was comparatively less than during seated cycling, which could have accounted for the extended time to fatigue during STD (Ryschon and Stray-Gundersen, 1991; and Tanaka et al., 1987). Variations in perceived feelings might have been due to the redistribution of the workload over a greater muscle mass and alterations in the muscle recruitment pattern (Ryschon and Stray-Gundersen, 1991).

Another factor that may have contributed to greater VO₂max during STD is the increase in joint angles when the individual comes out of the saddle and performs standing cycling. When standing, the hip, knee, and ankle joint excursions increase, which provides a greater range of motion within the respective joints (Nordeen-Snyder, 1977). Although not measured in the current study, it is possible that increases in the hip, knee, and ankle joint angles allowed for a more advantageous muscular force production and subsequent extended time to fatigue (Heil, Derrick, and Whittlesey, 1997; Nordeen-Snyder, 1977; and Shennum and deVries, 1976).

Millet et al. (2002), Tanaka et al. (1996), and Ryschon and Stray-Gundersen (1991) showed greater standing cycle ergometry HR. Although those differences occurred during a 4% incline protocol, significantly greater HR (1.2%) occurred during the current study, which utilized a level protocol. The extended time to fatigue allowed by standing may have attributed to a higher HR because earlier termination of the test due to leg fatigue and discomfort may have interfered with attainment of a true max HR.

Although only approaching significance (p = 0.08), an 0.83% greater VO_E occurred during STD compared to SIT. The increases in VO_E can be attributed to some of the reasons that likely contributed to a greater VO₂max during standing cycle ergometry. Generally when VO_E increases, so too does VO₂ (Foss and Keteyian, 1998).

As previously mentioned, when an individual leaves the seated cycle ergomerty position to stand, a greater involvement of upper and lower body muscle mass occurs. The activation of more muscle mass may allow for greater work output (Reiser, et al., 2002), which increases oxygen requirements of the muscles. In turn, ventilation increases. Cardiac output is also increased when participating in the standing position, which contributes to higher VO₂max and VO_E (Kelly et al., 1980). Also, because lower leg fatigue may be altered in the standing position, VO_E increases, and subjects are able to extend time to exhaustion.

For RER, SIT showed a significantly greater (2.3%) RER as compared to STD. Although SIT produced significantly greater RER compared to STD, the difference was of little practical significance. All RER values in both STD and SIT surpassed the criteria indicative of a “true” VO₂max (+1.15).

The current study showed that VO₂max_STD and HR_STD were significantly greater compared to SIT. However, despite the significant differences, it is important to note that discrepancies between the present study and previous studies (Montgomery et al., 1971 and Tanaka et al., 1996) could be a result of the protocol differences, variations in fitness levels, and low subject numbers. Many subjects benefited from the STD protocol as 20 of 36 (55.6%) individuals had greater VO₂max (up to 13.6%) and 25 of 36 (69.4%) subjects had greater peak HR (up to 7.4%). While means were significantly different, it should be noted that inter-individual variability was high. Some subjects had a much lower VO₂max during STD. Differentiating between those who respond positively and those who respond negatively to a standing protocol is difficult and was beyond the scope of the current study.

Conclusions:

The results of the current study support previous findings, showing a greater VO₂max during standing versus seated cycle ergometry (Kelly et al., 1980; Nakadomo et al., 1987; and Tanaka et al., 1987). Results of the current study also show significantly greater HR_STD. The current results support the use of a test protocol that allows an individual to stand during a cycle ergometry GXT. Therefore, since a higher VO₂max value was elicited using the standing protocol in the current study, a standing protocol should be considered for implementation when individuals are assessed for cardiorespiratory responses to maximal work using cycle ergometry. Future research should seek to determine characteristics of subjects who do/do not benefit from a standing versus seated protocol.

References:

Basset, D. R., and Howley, E. T. (2000). Limiting factors for maximum oxygen uptake and determinants of endurance performance. Medicine and Science in Sports and Exercise, 32, 70-84.

Beasley, J. C., Fernhall, B., and Plowman, S. (1989). Effects of optimized and standard cycling ergometry on VO₂max in trained cyclists and runners. Research Quarterly For Exercise and Sport, 60, 373-378.

Coast, J. R., Cox, R. H., and Welch, H. G. (1986). Optimal pedaling rate in prolonged bouts of cycle ergometry. Medicine and Science in Sports and Exercise, 18, 225-230.

Faria, I., Dix, C., and Frazer, C. (1978). Effect of body position during cycling on heart rate, pulmonary ventilation, oxygen uptake, and work output. Journal of Sports Medicine, 18, 49-56.

Fernhall, B., and Kohrt, W. (1990). The effect of training specificity on maximal and submaximal physiological responses to treadmill and cycle ergometry. The Journal of Sports Medicine and Physical Fitness, 30, 268-275.

Foss, M. L., and Keteyian, S. J. (1998). Fox’s Physiological Basis for Exercise and Sport. Ann Arbor, MI: McGraw-Hill.

Hagan, R. D., Weis, S. E., and Raven, P. B. (1992). Effect of pedal rate on cardiorespiratory responses during continuous exercise. Medicine and Science in Sports and Exercise, 24, 1088-1095.

Heil, D. P., Derrick, T. R., and Whittlesey, S. (1997). The relationship between preferred and optimal positioning during submaximal cycle ergometry. European Journal of Applied Physiology, 75, 160-165.

Kelly, J. M., Serfass, C., and Stull, G. A. (1980). Elicitation of maximal oxygen uptake from standing bicycle ergometry. Research Quarterly for Exercise and Sport, 51, 315-322.

Lavoie, N. F., Mahony, M. D., and Marmelic, L. S. (1978). Maximal oxygen uptake on a bicycle ergometer without toe stirrups and with toe stirrups versus a treadmill. Canadian Journal of Applied Sport Sciences, 3, 99-102.

Marsh, A. P., and Martin, P. E. (1993). The association between cycling experience and preferred and most economical cadences. Medicine and Science in Sports and Exercise, 11, 1269-1274.

McArdle, W. D., Katch, F. I., and Katch, V. L. (2006). Exercise Physiology: Energy, Nutrition, and Human Performance, 6th edition. Baltimore, MD: Lippincott, Williams, and Wilkins.

McKay, G. A., and Banister, E. W. (1976). A comparison of maximal oxygen uptake determination by cycle ergometry at various pedaling frequencies and by treadmill running at various speeds. European Journal of Applied Physiology, 35, 191-200.

McLester, J.R., Green, J.M., and Chouinard, J.L. (2004). Effects of standing vs. seated posture on repeated wingate performance. Journal of Strength and Conditioning Research, 18, 816-820.

Millet, G.P., Tronche, C., Fuster, N., and Candau, R. (2002). Level ground and uphill cycling efficiency in seated and standing positions. Medicine and Science in Sports and Exercise, 34, 1645-1652.

Moffat, R. S., and Sparling, P. B. (1985). Effect of toe clips during bicycle ergometry on VO₂max. Research Quarterly for Exercise and Sport, 56, 54-57.

Montgomery, S., Titlow, L. W., and Johnson, D. J. (1971). Estimation of maximal oxygen consumption from a stand-up bicycle test. Journal of Sports Medicine and Physical Fitness, 18, 271-276.

Nakadomo, F., Tanaka, K., Watanabe, H., and Fukuda, T. (1987). Maximal oxygen uptake measured during standing cycling with toe-stirrups. Kyoiku Igaku, 31, 18-23.

Nickleberry, B. L., and Brooks, G. A. (1996). No effect of cycling experience on leg cycle ergometer efficiency. Medicine and Science in Sports and Exercise, 28, 1396-1401.

Nordeen-Snyder, K. S. (1977). The effect of bicycle seat height variation upon oxygen consumption and lower limb kinematics. Medicine and Science in Sports and Exercise, 9, 113-117.

Pivarnik, J. M., Mountain, S. J., Graves, J. E., and Pollock, M. L. (1988). Effects of pedal speed during incremental cycle ergometer exercise. Research Quarterly for Exercise and Sport, 59, 73-77.

Pollock, M. L., Schmidt, D. H., and Jackson, A. S. (1980). Measurement of cardiorespiratory fitness and body composition in the clinical setting. Comprehensive Therapy, 6, 12-27.

Reiser, R.F., Maines, J.M., Eisenmann, J.C., and Wilkinson, J.G. (2002). Standing and seated wingate protocols in human cycling: a comparison of standard parameters. European Journal of Applied Physiology, 88, 152-157.

Ricci, J., and Leger, L. A. (1983). VO₂max of cyclists from treadmill, bicycle ergometer, and velodrome tests. European Journal of Applied Physiology, 50, 283-289.

Ryschon, T. W., and Stray-Gundersen, J. (1991). The effect of body position on the energy cost of cycling. Medicine and Science in Sports and Exercise, 23, 949-953.

Shennum, P. L., and deVries, H. A. (1976). The effect of saddle height on oxygen consumption during bicycle ergometer work. Medicine and Science in Sports and Exercise, 8, 119-121.

Swain DP, and Wilcox JP (1992). Effect of cadence on the economy of uphill cycling. Medicine and Science in Sports and Exercise, 24: 1123-1127

Tanaka, H., Bassett, D. R., Best, S. K., and Baker, K. R. (1996). Seated versus standing cycling in competitive road cyclists: uphill climbing and maximal oxygen uptake. Canadian Journal of Applied Physiology, 21, 149-154.

Tanaka, K., and Maeda, K. (1984). A comparison of maximal oxygen uptake during standing cycling and uphill running. Japanese Journal of Applied Physiology, 14, 215-219.

Tanaka, K., Nakadomo, F., and Moritani, T. (1987). Effects of standing cycling and the use of toe stirrups on maximal oxygen uptake. European Journal of Applied Physiology, 56, 699-703.

Verstappen, F. T. J., Huppertz, R. M., and Snoeckx, L. H. E. H. (1982). Effect of training specificity on maximal treadmill and bicycle ergometer exercise. International Journal of Sports Medicine, 3, 43-46.

Welbergen, E., and Clijsen, L. P. V. M. (1990). The influence of body position on maximal performance in cycling. European Journal of Applied Physiology, 61, 138-142.

U.S. Sports Academy2017-08-07T11:47:23-05:00March 14th, 2008|Contemporary Sports Issues, Sports Coaching, Sports Exercise Science, Sports Studies and Sports Psychology|Comments Off

Acclimatization in High-Altitude Sport: Predictive Modeling of Oxygen Saturation as an Expedition Management Tool

Submitted by: Dave Valliere & Norm O’Reilly

Abstract:

A management perspective is taken in developing a predictive model to forecast blood oxygen saturation levels for trekkers and mountaineers ascending to high altitudes. Blood oxygen saturation is an important indicator of risk of acute mountain sickness and other potentially lethal health risks for high-altitude athletes. This model is based on data collected from a seventeen-person expedition to Mt. Everest. The results of the model are compared to actual saturation levels and the model is found to be a good predictor. The practical implication is that an oximeter and the results it produces are useful tools for expedition managers and base camp managers charged with the safety of a multi-person expedition.

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U.S. Sports Academy2018-06-05T09:12:13-05:00March 14th, 2008|Sports Exercise Science|Comments Off

The Effect of a Plyometrics Program Intervention on Skating Speed in Junior Hockey Players

Submitted by: Kelly L. Lockwood & Patrick Brophey

Abstract

Few studies have been conducted to examine the effects of plyometrics on skating speed in junior hockey players. The present study was designed to look at the effects of a 4-week, eight session, plyometric training program intervention on skating speed. Six male subjects (18.8 ± .98 years) that engaged in the training program completed pre and post 40 meter on-ice sprinting tests. The training group showed significant time improvements (p<.05) in the 40 meter skating distance. The results suggested that plyometric training has a positive effect on skating speed in junior hockey players such that a reduction in on-ice sprinting times is evident.

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U.S. Sports Academy2016-10-24T11:45:30-05:00March 3rd, 2008|Contemporary Sports Issues, Sports Coaching, Sports Exercise Science, Sports Studies and Sports Psychology|Comments Off

Plyometrics, or Jump Training for Dancers

Submitted by: Brenda G. Griner, Douglas Boatwright, and Dan Howell

One question that many dancers ask is, “How can I get my jumps higher?” The repetitive execution of demi-plie is used to improve timing, alignment, strength, torso stability, and coordination of joint movement; it is also a first component of other movements, such as pirouette, releve, and all aerial movements (Trepman, Gellman, Micheli, & De Luca, 1998). Four principles must be applied when executing jumps of any kind. First, any jump must begin in demi-plie. Second, in order to take the jump into the air, the dancer must press off the floor by fully pointing the foot. Third, the dancer must land on the balls of the feet, rolling through to the heels. Fourth, the jump must end in demi-plie (Kraines & Pryor, 2001).

Little information is found analyzing how dancers use their muscles to perform highly trained movements such as leaps and jumps. Instead, most studies focus on the treatment of injuries sustained by dancers (Trepman et al., 1998). Some injuries, according to Hobby and Hoffmaster (1986), involve “muscle imbalances” resulting from dance training that “places specific demands on . . . bodies” (p. 39). Incorrect training can, in other words, produce underdeveloped or overdeveloped muscle groups. A study by Simpson and Kanter (1997) indicated that injury to lower extremities is common among dancers pursuing various forms of dance, for instance modern dance, jazz dance, and ballet. It linked chronic dance injuries to improper landing when jumping.

Many of the skills required in dance are also used in sports like figure skating and gymnastics (McQueen, 1986). Certain sport training techniques, therefore, can be useful to dancers (McQueen, 1986). Fahey (2000) noted that, “Jumping exercises and plyometrics enhance performance in strength-speed sports because they increase leg power and train the nervous system to activate large muscle groups when you move” (p. 76). Hutchinson and colleagues’ study of elite gymnasts suggested that leap training utilizing a swimming pool as well as Pilates safely enhanced leaping ability (Hutchinson, Tremain, Christiansen, & Beitzel, 1998). In the study, after one month of training, gymnasts improved their explosive power by 220%, their ground reaction time by 50%, and the height of their leaps by 16.2%.

The objective of plyometrics is to generate the greatest amount of force in the shortest amount of time (Seabourne, 2000). Plyometrics trains the nervous system and metabolic pathways to increase explosiveness, giving the athlete an extra push to move higher and faster. Plyometrics requires acceleration through a complete range of motion, followed by relaxation into a full stretch. The quick stretch applied to the muscle by the athlete during initial push-off is thought to increase muscle contraction, in turn increasing power. The Cincinnati SportsMedicine and Orthopaedic Center has developed a plyometrics-based program called Sportsmetrics, which has been shown to increase jump height and decrease harmful landings (Hewett & Noyes, 1998). Hewett, Stroupe, and Riccobene (1999) analyzed the effects of 6 weeks of Sportsmetrics training in female athletes, finding that, after completing the program, the athletes’ peak landing forces decreased by 22%, lateral and medial forces at the knee dropped by 50%, and the height of jumps increased 10%. Furthermore, hamstring-to-quadriceps strength ratio rose from 50% to 66%, creating “a more favorable condition for the ACL [anterior cruciate ligament]” (Boden, Griffin, & Garrett, 2000, p. 57). Plyometrics training has been shown to generate greater strength output with fewer injuries, and the present study’s purpose was to assess the effects of a 7-week plyometrics program on the vertical jumps and leaps executed by collegiate dancers.

]Method[

With approval of the appropriate human subjects review board, a sample of 12 female members of a Division I college dance team participated in a plyometrics training program. The specific program used was the Cincinnati SportsMedicine and Orthopaedic Center’s Sportsmetrics program, in which the dancers participated for 7 weeks. Vertical jumps were measured using a Vertec vertical height measuring device. Strength measurements were made using a CYBEX II isokinetic testing and rehabilitation system and HUMAC software for CYBEX by CSMI.

Initially, a meeting was convened during which the Sportsmetrics program was explained in detail to the 12 participants. They were told that the program would be used 3 times a week for 7 weeks. The program featured approximately 40 min of various jumping exercises. Every week, the amount of time devoted to each exercise increased. The participants kept records of how many repetitions of each they completed. After completing the session, the participants continued with a rehearsal lasting 1–2 hr. Every two weeks, the participants were taught a new program of increased difficulty. The plyometrics program carried the dancers into the beginning of their regular season workouts and game performances.

The 12 participants completed a pretest consisting of a 5-min warm-up and 5-min stretch. Height and weight of each participant were recorded. For each participant a standing reach measurement was also obtained, as the participant stood with feet hip-width apart, eyes forward, and reached vertically, the dominant hand on top of the other hand, using the Vertec vertical height measuring device. Using the Vertec vertical height measuring device, each participant executed a standing two-leg jump; the best of three efforts was recorded.

Using the same device, a two-step leap off of the right leg and a two-step leap off of the left leg were evaluated. Participants stood behind the Vertec and attempted a run, run, leap off of the right leg, with the left leg flexed at the knee and the right hand reaching up. The foot was plantar flexed and placed against the medial side of the knee in passe position. The same leap was executed off of the left leg, with the right leg flexed at the knee.

To obtain strength measurements, the participants were evaluated in a sports medicine laboratory. Each dancer was first of all familiarized with the CYBEX II equipment. Standard protocols for measuring thigh strength with the CYBEX II were used. All posttest measurements were taken after the participants had completed 7 weeks of training. Pre- and posttest data were analyzed using a paired t test, with alpha set at 0.05.

]Results and Discussion[

There were five freshmen, one sophomore, four juniors, and two seniors on the dance team from which the study participants were drawn. The participants’ biometric data were as follows: age in years, 19.7 + 1.5; height in meters, 1.65 + 0.06; and weight in kilograms, 57.4 + 6.38. In posttests after 7 weeks of plyometrics training, the right quadriceps peak torque at 180 deg/s (M = 57.9 ft lb) was significantly higher than that from the pretest (M = 54.3 ft lb), t (11) = -2.435, p < .05. Furthermore, although the difference was not statistically significant, the change between pretest means for the left quadriceps peak torque at 180 deg/s (M = 54.2 ft lb) and posttest means (M = 57.8 ft lb) did indicate improvement, t (11) = -1.904, p > .05. Vertical jump measures taken after 7 weeks of plyometrics training indicated a significant difference, t (11) = -4.59, p < .05. Also noted was significant improvement in the two-step jump off the right foot, t (11) = -2.5, p < .05. No such improvement was noted for the two-step jump off the left foot, t (11) = -1.05, p > .05.

Thus after 7 weeks of plyometrics training, there were increases in strength in the right leg at 180 deg/s. Strength in the left leg also showed improvement in peak torque performance at 180 deg/s, although not at the level of significance. Significant improvement was seen for the vertical jump and the two-step jump off the right foot.

Most dance teachers teach leaps off of both feet, off the left foot, and off the right foot. However, because many dancers jump off the left foot when executing leaps in classroom combinations at center or in performance, many if not most dancers may exhibit an imbalance in lower limb strength. The 7-week plyometrics program employed in this study may have diminished any imbalance of strength in these dancers.

Further investigation with other dancers is warranted on this topic. It may prove useful to test dancers in middle school, high school, and college. In addition, it may be beneficial not only to take isokinetic strength measures, but a measure of isometric strength as well. The possibility that dance training may develop lower-limb muscle imbalances in dancers should be investigated, as should the usefulness of plyometrics training for younger dancers to prevent any such imbalances.

]References[

Boden, B. P., Griffin, L. Y., & Garrett, W. E. (2000). Etiology and prevention of noncontact ACL injury. The Physician and Sportsmedicine, 28(4), 53–50.

Fahey, T. D. (2000). Super fitness for sports, conditioning, and health. Needham Heights, MA: Allyn and Bacon.

Hewett, T. E., & Noyes, F. (1998). Cincinnati Sportsmetrics: A jump training program proven to prevent knee injury [Motion picture]. United States: Cincinnati (Ohio) SportsMedicine Research and Education Foundation.

Hewett, T. E., Stroupe, A. L., & Nance, T. A. (1996). Plyometric training in female athletes: A prospective study. American Journal of Sports Medicine, 24(6), 765–773.

Hobby, K., & Hoffmaster, L. (1986). In D. Paterson, G. Lapenskie, & A. W. Taylor (eds.), The medical aspects of dance. London, Ontario, Canada: Sports Dynamics.

Hutchinson, M. R., Tremain, L., Christiansen, J., & Beitzel, J. (1998). Improving leaping ability in elite rhythmic gymnasts. Medicine and Science in Sports and Exercise, 30, 1543–1547.

Kraines, M. G., & Pryor, E. (2001). Jump into jazz: The basics and beyond for the jazz student (4th ed). Mountain View, CA: Mayfield.

McQueen, C. (1986). In D. Paterson, G. Lapenskie, & A. W. Taylor (eds.), The medical aspects of dance. London, Ontario, Canada: Sports Dynamics.

Seabourne, T. (2000). The power of plyometrics. American Fitness, 18, 64–66.

Simpson, K. J., & Kanter, L. (1997). Jump distance of dance landings influencing internal joint forces: I. axial forces. Medicine and Science in Sports and Exercise, 29, 916–927.

Trepman, E., Gellman, R. E., Micheli, L. J., & De Luca, C. J. (1998). Electromyographic analysis of grand plie in ballet and modern dancers. Medicine and Science in Sports and Exercise, 30(12), 1708–1720.

Author Note

Brenda G. Griner, Department of Health and Kinesiology and Department of Music, Theater, and Dance, Lamar University; Douglas Boatwright, Department of Health and Kinesiology, Lamar University; Dan Howell, Department of Health and Kinesiology, Lamar University, and Beaumont (Texas) Bone and Joint.

U.S. Sports Academy2017-08-07T11:50:44-05:00February 22nd, 2008|Sports Coaching, Sports Exercise Science|Comments Off