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Anaerobic Power in Female Athletes
Sports Physiology
Assessment of Anaerobic Power in Female Division I Collegiate Basketball Players
KORY STAUFFER1, ELIZABETH NAGLE 2, FREDRIC GOSS 2, ROBERT ROBERTSON 2
1Department of Sport and Exercise Science, Gannon University, Erie, PA, USA2, Department of Health and Physical Activity, University of Pittsburgh, Pittsburgh,Pa, USA
ABSTRACT
Stauffer KA, Nagle EF, Goss FL, Robertson RJ. Assessment of Anaerobic Power in Female Division I Collegiate Basketball Players. JEPonline 2010;13(1): 1-9.Previous test batteries have attempted to accurately measure anaerobic power output in basketball players. At present, there is no standard criterion measure that has demonstrated strong validity or application as a sport specific measure of power. Therefore, the purpose of this study was to determine whether a significant relation exists between the Max Jones Quad test and two established anaerobic power tests in a sample of female Division I basketball players. Subjects (19.7 ± 1.1 years) reported for testing on three separate days. Body composition and the vertical jump test were performed on Day 1. The Max Jones Quadrathalon Test (MJQT), which consists of the following four stations: 1) standing broad jump; 2) three consecutive broad jumps; 3) overhead shot put toss; and 4) 30-meter sprint, was administered on Day 2. Subjects performed a 30-second Wingate cycle ergometer test on Day 3. A significant relation (p<0.05) was found between anaerobic power (Wingate cycle test) and only one of the Max Jones Quad test components (30-meter sprint) (r = -0.57). Additionally, correlations between vertical jump height and Max Jones Quad test components were found to be significant (p<0.05; p<0.01) (broad jump, r = 0.64; 3 broad jump, r = 0.56; 30m sprint, r = 0.69; Total Score, r = 0.70).These results suggest that certain components of the Max Jones Quad test are related to anaerobic power output. Further investigation of the usefulness of the Max Jones Quad test as a sport specific measure of anaerobic power is warranted.
Key Words: Sport Performance, Wingate, Vertical Jump.
INTRODUCTION
Physiological measures that incorporate cardiovascular, neuromuscular, and metabolic components are necessary to determine anaerobic power, considered an integral contributor to athletic performance (6). The ability of a body’s musculature to generate significant amounts of power is considered to be a strong predictor of athletic success (3). As a laboratory measure, the Wingate anaerobic cycle ergometer power test is considered the most valid and reliable instrument to assess peak power and anaerobic capacity (1,12,17). The most common field tests used to evaluate anaerobic power and performance in athletes are the vertical jump test (1,6)and the 40-yard dash (1). However, sport specific anaerobic field tests to assess power output have not been established. In order to properly assess anaerobic characteristics, sport specific activities should be employed on athletes.
The Max Jones Quadrathalon, or Quad test, was developed in 1982 by Max Jones, a national Olympic throws coach for England’s Track and Field team. The Quadrathalon was devised to test explosive power improvement of the Great Britain National Throws Squad (8). Considered relatively easy to administer, the Quad test has been used primarily to test Division I track and field and football athletes. When first developed, it was intended to be used to gauge an athlete’s improvement in power throughout the off-season. The Quadrathalon consists of a series of drills (1) Standing long (broad) jump; 2) Three consecutive standing long (broad) jumps; 3) Thirty meter sprint; and 4) Sixteen pound overhead shot-put throw) used to assess an athlete’s speed, strength, explosiveness, and power.
The Max Jones Quad Test has not been compared to established anaerobic power tests, and therefore its validity as a measure of anaerobic power has not been documented. In general, the Quad test has only been used to assess power performance in male track and field athletes and football players in non-research settings. The Quad test has not been used to evaluate the anaerobic power of female athletes, and in particular Division I basketball players. It was anticipated that the Quad test would be an effective tool in assessing anaerobic power in basketball athletes since it presents components that are sport specific. Sprinting and jumping activities are essential in basketball performance and should be included in assessment measures. Therefore, the purpose of this study was to determine whether significant relations exist between components of the Quad Test and the Wingate cycle and Vertical Jump tests.
METHODS
Subjects
Thirteen membersof the University of Pittsburgh Women’s Division I basketball team currently participating in basketball and conditioning activities were recruited for this investigation. All participation was voluntary and had support and approval of the University of Pittsburgh Department of Athletics, head women’s Basketball Coach, and strength and conditioning coach. At the time of testing, all athletes had undergone six weeks of pre-season training. The University of Pittsburgh Institutional Review Board (IRB) approved all procedures prior to data collection.
Procedures
Subjects reported for testing on three consecutive days. On the first day, subjects were provided an overview of the study once written informed consent was obtained. Athletes then had the opportunity to ask questions about the tests they would be performing. Body composition was assessed at the orientation session using a Tanita bioelectrical impedance analyzer (BIA) scale. The Tanita scale was set to Athletic Mode and subjects stood on the scale for approximately 10 seconds. Two trials were performed for each subject and an average of the two measures was used to determine accurate body compositions. Prior to testing, subjects were led through an 8-10 minute dynamic warm-upconsisting of exercises for all major muscle groups. The vertical jump was performed as described in the laboratory protocol of Adams (1) on a Vertec standing jump scale. Subjects were allowed one quick dip (i.e. countermovement) of the knees and one arm swing. The subject executed the jump while touching or swatting the measuring vanes on the Vertec at the peak of the jump. The jumper’s hand caused several of the measuring vanes to be displaced near the peak of the jump. Subjects were allowed thirty seconds in between jump trials to ensure recovery. Jump trials were continued until subjects did not exhibit an increase in jump height, usually within three to five jumps. Peak and average anaerobic power output were calculated for the vertical jump test using equations developed by Johnson and Bahamonde (13).
On the second day, the Max Jones Quad Test tests were conducted on the Astroturf surface in the CharlesL.CostSportsCenter’s indoor regulation sized football field on the campus of the University of Pittsburgh. Prior to testing, subjects were led through an 8-10 minute dynamic warm-upidentical to the warm-up for the vertical jump test. The Max Jones Quad Test was explained in detail and demonstrated to the group. Subjects were then permitted to familiarize themselves with the various movements associated with the test. Next, subjects performed the Quad test consisting of four stations: 1) standing broad jump; 2) three consecutive broad jumps; 3) overhead shot put toss; and 4) 30 meter sprint. Standing broad jump, three consecutive broad jumps, and overhead shot put toss were measured in meters (m) and centimeters (cm), respectively. Subjects were allowed thirty seconds in between each trial to ensure recovery. An active recovery also took place when the subjects rotated between each station. In order to minimize fatigue, the broad jump, 3 consecutive broad jumps, and overhead shot put were done before the 30-meter sprint. Each component of the Max Jones Quad Test was individually scored based on the distance or time recorded. These scores were obtained by matching the test distance or time with its appropriate individual standardized score. The four individual event scores were then totaled to obtain an overall score for the Max Jones Quad Test. (See included scoring chart).
On the final day, maximal anaerobic power of the lower body was evaluated by the Wingate anaerobic cycle test on a Monark 828 E cycle ergometer (Monark Exercise AB, Sweden).Prior to the Wingate anaerobic cycle test, the subjects were lead through an 8-10 minute dynamic warm-up that consisted of exercises previously described. Subjects performed a 30-second Wingate cycle ergometer test using a modified version of the original Wingate anaerobic cycle ergometer test (12). A shorter warm-up consisting of two to four minutes of pedaling interspersed with two to three maximal sprints each lasting four to eight seconds was used to prepare the subject. Force selection for this investigation was 0.090 kg . kg of body mass-1 (0.90 N) based on recommendations by Adams (3) for anaerobically fit female persons. Once the prescribed force was reached, the force-setter yelled “go” and the timer officially started the clock to begin the test. The subject began pedaling as fast as possible for a 30-second period while remaining seated on the bike for the duration of the test. The resistance was reduced to a cool-down recovery setting (between 1 and 2 kg) while the subject continued to pedal at about 50 rpm for 2 to 3 minutes. Values of anaerobic power (peak and mean power; fatigue index) were determined by the SMI Optosensor (Sports Medicine Industries, Inc., St. Cloud, MN). Peak power is the greatest power output during a five second period during the test (usually seen in the first five seconds). Mean power is the average power output over the course of the entire thirty seconds. Fatigue index represents the percent decrease in power output from the beginning of the test to the end of the test. The SMI Power software calculated power output for each second of the test as a function of the resistance load applied to the flywheel and the velocity of the flywheel. Revolutions of the flywheel were measured with an optical sensor attached to the Monark frame.
Statistical Analyses
Data analysis was performed using SPSS 11.0 for Windows statistical software. Using a power of 0.80 and an α level of 0.05, a sample size of 16 subjects was needed for a significant correlation (r = 0.60). Subject characteristics and experimental variables were calculated as mean ± SD. Results from the anaerobic power tests were analysed for the entire subject cohort and by individual player position: 1) Guards (n=6); 2) Forwards (n=4); and 3) Centers (n=3). In addition, Pearson product-moment correlations were calculated between the overall Max Jones Quad Test score and Wingate cycle ergometer as well as the Vertical jump test.
RESULTS
Thirteen members of the University of Pittsburgh Women’s Division I basketball team participated in this investigation and were assigned to one of three groups based on the position they played. Subject descriptive data are presented in Table 1.
A significant correlation (r = 0.85) was found between peak power measured with the Vertical Jump and the Wingate anaerobic power tests. A non-significant negative correlation (r=-0.31) was found between peak anaerobic power measured by the Wingate cycle test and total Max Jones Quad Test score. No significant correlation (r = -0.02) was found between peak anaerobic power measured with the vertical jump test and total Max Jones Quad Test score. However, a significant (p < 0.05)negative correlation (r = -0.57) was found between the Wingate Cycle Test and the 30-meter sprint component. The results of the correlation between anaerobic power determined by vertical jump and the Wingate test and individual scores and total score for each component of the Max Jones Quad Test are presented in Table 2.
Vertical Jump
A significant correlation (p < 0.05; p < 0.01)was found between vertical jump height and broad jump score (r = 0.637), three broad jump score (r = 0.556), 30-meter sprint score (r = 0.687), and total score (r = 0.696). Table 3 presents correlations between vertical jump height and individual scores on the Max Jones Quad Test. Table 4 presents the correlations between vertical jump height and absolute measures, in meters or seconds, for each Max Jones Quad Test component.
DISCUSSION
Current Measures of Anaerobic Power Performance
It has been estimated that the energy system contributions for the sport of basketball are approximately 80% ATP-PC, 10% anaerobic glycolysis, and 10% aerobic (9). Considering that the majority of energy in basketball performance is generated from anaerobic sources, the implementation of tests that assess anaerobic attributes of basketball players would be of great value. In the current investigation, a significant correlation (r = 0.85) was found between peak power measured during the Vertical Jump and Wingate anaerobic power tests, demonstrating the validity of the Vertical Jump as a field test of anaerobic power. Both tests rely heavily on ATP/PC energy system to produce and sustain anaerobic power (9).
In addition, body weight had a considerable impact on performance of these two tests. Heavier subjects in the current investigation had higher anaerobic power outputs on both the Vertical Jump and Wingate tests. The results of the correlation between anthropometric measurements and anaerobic power tests are presented in Table 4. Positive correlations such as these between the Vertical Jump and Wingate anaerobic power tests have been seen in previous investigations (2,7,11). The Vertical jump and Wingate anaerobic power tests have been administered to athletes and recreationally active individuals, and are considered relatively valid and reliable. Yet, a need remains to identify valid sport specific tests that can provide a better overall measure of anaerobic power.
Max Jones Quadrathlon vs. Vertical Jump and Wingate Cycle Power Output
In general, correlations between Max Jones Quad Test components and peak power outputs from the vertical jump and Wingate cycle tests were extremely weak and not anticipated (r = -0.02 to r = 0.43). The only significant relation occurred between the Wingate cycle test and the 30-meter sprint
(r = -0.57). The poor relation between the Max Jones test and peak power on the Vertical Jump and Wingate cycle tests may be explained by a discrepancy in physiological requirements. When performing the vertical jump and Wingate cycle tests, the subjects in the present study with greater heights and/or weights exhibited the ability to generate greater power outputs. The prediction equation used to determine anaerobic power based on vertical jump height also used height and weight as variables. This suggests that individuals taller and/or heavier would be predicted to a have higher anaerobic power output. On the contrary, these same physical characteristics were found to be detrimental to an individual’s performance on the Max Jones Quad Test determined by the current investigation. The poor relationship between the Max Jones Quad test and the other anaerobic power tests can also be attributed to a relative lack of experience with the four components of the test. Practice time for the Max Jones Quadrathlon was allotted on the second day of testing. While subjects demonstrated sufficient knowledge on how to perform each component, a possibility exists that a lack of practice time to learn and execute each component to the best of their ability may have occurred.
Max Jones Quadrathlon vs. Vertical Jump Height
As expected, significant relationships were observed between component and total scores (points) and absolute measures of the Max Jones Quadrathlon when compared with vertical jump height. Correlation coefficients ranged from r = 0.56 to r = 0.69 on individual scores and from
r = 0.58 to r = -0.69 on absolute measures for Max Jones test components (p < 0.05 level (standing broad jump and three broad jump); p< 0.01 level (30-meter sprint)). Research has shown significant correlations between vertical jump height and standing long jump distance in female (15,16) and male (2,10,14,18) college students.
Significant relationships have also been found between vertical jump height and short sprint distances in female (15) and male (2,14,18) college age students.
The standing broad jump and vertical jump share similar biomechanical properties, with the primary difference being that force generated during the standing broad jump is exerted to move the body horizontally, rather than vertically (10). Conventional thinking suggests that individuals who perform better on short sprints and jumping activities possess greater amounts of fast twitch muscle fibers (4,5). This may help to explain why a significant relation was seen between vertical jump height and 30-meter sprint time.
Limitations
The present study contained certain limitations that may have contributed to the results observed. First, sample size was restricted since the basketball team included only thirteen members on its roster. The small sample size decreased the overall power of the study and did not allow for randomization. This in turn affected the internal validity of the study. Second, the resistance selection for the Wingate cycle test administered in the current investigation was 0.090 kg . kg of body mass-1 (0.90 N). This resistance is recommended for anaerobically fit female athletes (1). However, it was observed that several of the basketball players in the present study struggled with this resistance setting, which might have contributed to lower absolute power outputs. Third, performance on certain tests may have been influenced by a lack of sport specificity. An all out sprint on a cycle ergometer or throwing a weighted implement backwards over one’s head are not requirements of female basketball players during competition. Sport specific movements that mimic common functional activities needed to compete in women’s basketball may have been more appropriate. Lastly, the amount of practice time allowed for both the Wingate cycle test and the Max Jones Quad Test may have limited the overall performance on these two tests.