2012 Undergraduate Research
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The effect of caffeine on anaerobic performance: a preliminary study |
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Correlation of diagonal bounding and vertical jump with on-ice acceleration in female collegiate hockey players Vertical jump is a test that is often used to predict on-ice acceleration in hockey players. However, because diagonal bounding more closely resembles the movement pattern associated with hockey skating, it is hypothesized that diagonal bounding time may be more strongly correlated to on-ice acceleration. The purpose of this study was to examine the relationship between on-ice sprint times, dry-land diagonal bounding times, and countermovement jump height. Seventeen Division III female hockey players participated in the study. Participants performed three on-ice 6.1 meter sprint trials and three dry-land 6.1 meter diagonal bounding trials, each measured with a Brower electronic timing system. The best time for each athlete from each set of trials was used in this study. Participants perform multiple trials of the countermovement vertical jump test until they failed to improve their jump height on two consecutive trials. The maximum vertical jump height, measured in inches using a Vertec device, was used in this study. The mean on-ice sprint time, diagonal bounding time, and vertical jump height were 1.47 s (±0.09s), 1.97 s (±0.29 s), 42.49 cm (±4.93 cm), respectively. A Pearson correlation revealed an insignificant positive correlation between vertical jump height and on-ice acceleration time (r = .139, p > .05) and an insignificant negative correlation between diagonal bounding time and on-ice acceleration time (r = -.224, p > .05). The results suggest that vertical jump height and diagonal bounding time are poor predictors of on-ice acceleration for Division III female hockey players. |
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Do division III cross country runners experience the intended coach prescribed training impulse (TRIMP)? Cross country coaches create training plans to induce desired adaptations. However, research suggests athletes do not consistently train as the coach prescribed. The purpose of this study was to examine the relationship between coach intended (CI), athlete-perceived (AP) and physiological (P) training impulses (TRIMP) during recovery (R), slow long distance (SLD), tempo (T) and interval (I) training performed by 14 Division III female cross country runners. A TRIMP weighting scale was created for each athlete based on her blood lactate curve. Heart rate data were collected using Polar Team System heart rate monitors during a two week in season period. The P TRIMPs were calculated by multiplying time spent in each heart rate zone by the assigned weighting factor. The CI TRIMPs for each practice session were calculated using the prescribed running intensity based on intended rate of perceived exertion (RPE) multiplied by duration. The AP TRIMPs were calculated using session RPE multiplied by duration. One-way ANOVA revealed significant differences in the mean TRIMPs for R [(F (2,204) = 3.359, p = .037)], T [(F (2, 75) = 19.034; p < .001)], and I [(F (2, 55) = 4.161, p = .021)] training, but not for SLD training [(F (2, 60) = 1.089, p = .343)]. Post-hoc testing revealed a significant difference (p = .019) in the mean CI (M = 52.52, SD = 29.73) and P (M = 65.80, SD = 32.50) TRIMPs during R training. Also, significant differences (p < .001; p = .006) in the mean CI (M = 109.87, SD = 26.54; M = 72.17, SD = 38.16) and AP (M = 6.77, SD = 30.37; M = 41.93, SD = 26.21) TRIMPs were found during T and I training, respectively. These results suggest participants trained at intensities higher than coach prescribed during R training. During T and I training, athletes ran at the coach indicated intensity, but perceived themselves to be training at a lower intensity. The results indicate a need to more closely monitor intensity during R training to ensure proper recovery. |
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Use of rate of perceived exertion measured during progressive treadmill testing Rate of perceived exertion (RPE) is a method used by coaches to prescribe exercise intensity. RPE is intended to correspond to a target heart rate (HR) range for the athlete. Often the HR/RPE relationship is determined using a progressive treadmill test. The purpose of this study was to examine the relationship between the athletes' reported session RPE and the momentary RPE during a progressive treadmill test. Fourteen Division III female cross country runners performed a progressive treadmill test at the beginning of the season. At two-minute intervals, heart rate and momentary RPE were recorded. During a two week period, participants wore Polar Team System HR monitors for recovery, long slow distance, tempo, and interval cross-country practices and reported session RPE at the end of each practice. The average HR for each practice was calculated and compared to the treadmill HR/RPE curve, which allowed us to compare the session RPE and momentary treadmill RPE at the corresponding HRs. A Pearson Correlation revealed a positive relationship between session RPE and treadmill RPE during recovery (r = .385) and long slow distance (r = .156) running. Negative correlations were observed for the more intense tempo (r = -.124) and interval (r = -.226) training. An RPE scale based on a shorter-duration progressive treadmill test is not a highly effective method for prescribing running intensity. Future research should investigate the reliability of HR/RPE scales that are based on progressive tests of comparable duration and environmental conditions as those of the subsequent exercise sessions. |
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Relationship between Rate of Perceived Exertion and Blood Lactate Concentration in Female Cross Country Runners Previous studies have found a strong correlation between the rate of perceived exertion (RPE) and blood lactate levels. However, the strength of this relationship has been shown to depend on the population. The purpose of this study was to examine how closely the RPE corresponds to blood lactate concentration in Division III female cross country runners during a progressive treadmill test. Fourteen Division III female cross country runners participated in this investigation. All participants finished in the top half of a 2.5 mile time trial at the beginning of the season. Each performed a progressive treadmill test to assess blood lactate levels and RPE, with blood sampling every two minutes. Pearson's correlation analysis revealed a significant, positive correlation between RPE and blood lactate levels [r(157) = .849, p < .001]. The strength of the relationship between RPE and blood lactate concentration in female cross country runners is stronger than that found in other active populations, such as soccer players. The results provide additional evidence that blood lactate concentration may be a physiological mediator for perception of exertion during dynamic exercise and may serve as a stronger mediator for female cross country runners compared to other active populations. |
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Calculating training impulse: A comparison of three methods Training impulse (TRIMP) is the product of exercise intensity and duration and is a method used to quantify training load. Several methods of calculating TRIMPs have been proposed, but no comparison of the results of the various methods have been reported. Therefore, the purpose of this study was to examine the strength of the relationship between the TRIMPs calculated by two methods reported in the literature and a novel method created for this study. Fourteen Division III female cross country runners participated in this study. All participants completed a progressive treadmill test with concurrent heart rate and RPE monitoring, and blood lactate testing every two minutes. Heart rate and blood lactate data were used to create a unique non-linear TRIMPs weighting scale for each athlete. For two consecutive weeks, heart rate data were collected using Polar Team System heart rate monitors during all coach prescribed running, including recovery (R); slow, long distance (SLD); tempo (T); and Interval (I) running. The TRIMP for each athlete during each training session was calculated using the three different calculation methods. Pearson bivariate correlations revealed a significant positive relationship (p < .001) between the TRIMPs associated with each of the calculation methods during R (r ranged from .727 to .844), SLD (r ranged from .706 to .855) and I (r ranged from .617 to .844) practice sessions. Tempo runs produced the greatest range in correlations (r ranged from.232 to .814). The results indicate strong positive relationships between the TRIMPs calculate by the three methods when the majority of the practice session heart rate data were below lactate threshold. However, when heart rates were near or above lactate threshold for the majority of the practice, the correlations between the methods were not as strong. The results of this study suggest that the three methods of calculating TRIMPs are not equivalent. Therefore coaches need to become aware of the advantages and disadvantages of each method. Future research should look to establish the most valid method of calculating TRIMPs across a spectrum of training intensities. |
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Optimal angle of knee flexion for maximal vertical jump in division III collegiate athletes Vertical jump is often used as a measure of lower body power. However, the validity of vertical jump test results may be affected by the athlete's jump technique, including knee flexion take-off angle. The purpose of this study was to measure the effect of three countermovement knee flexion take-off angles on vertical jump height. Twelve Division III male collegiate football players volunteered to participate in this study (18-22 years old). Participants performed three countermovement vertical jumps for each of the three trials: knee flexion take-off angle at 50, 80, and 110 degrees). Vertical jump height was measured to the nearest tenth of an inch with a Just Jump contact mat and converted to centimeters. Repeated measures ANOVA revealed a significant effect of knee flexion angle [F(2, 22) = 25.268, p ≤ 0.001]. A pairwise comparison revealed significant greater jump height when the knee flexion take-off angle was 80 degrees (67.417 ± 1.730 cm; p ≤ .001) and 110 degrees (68.791 ± 1.755 cm; p ≤ .001) compared to 50 degrees (61.595 ± 1.369 cm). No significance in vertical jump height was found between the 80 and 110 degree knee flexion take-off angle trials (p = .412). Therefore, a knee flexion take-off angle between 80 and 110 degrees appears to be advantageous in maximizing vertical jump height. |
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Anaerobic Performance in the absorptive and fasted states The aim of this experiment is to compare the effects of being fed or fasted on high-intensity treadmill exercise. Participants of the study will complete two trials of high-intensity treadmill running to exhaustion, once after consuming a standardized meal, and once after fasting for at least eight hours. Measurements include time to exhaustion, blood lactate and blood glucose before and after exercise, rate of perceived exertion (RPE), and heart rate. We expect to find shorter time to exhaustion, lower blood lactate, and higher RPE in the fasted trial. We also expect to find no differences in blood glucose and heart rate between the fed and fasted trials. |
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Effects of cold water immersion on competitive female dancers during 3 days of unaccustomed training Athletes training multiple times per day require fast, effective recovery methods. Cold water immersion (CWI) is commonly used by athletes to speed recovery and attenuate muscle soreness, edema, and inflammation in order to maintain performance during subsequent exercise bouts. The purpose of this study was to investigate the effects of post-exercise CWI during three days of unaccustomed intense training, on fatigue, perceived muscle soreness (PMS), flexibility, thigh circumference, vertical jump, agility, and anaerobic capacity in competitive female dancers. Twelve untrained female dancers (18-22 years old) completed three light to intense pre-season exercise sessions per day for three consecutive days. Morning workouts consisted of two hours of moderate to high intensity training, followed by either CWI (10 min at 10 C, N=7) of the lower body covering the hips and legs or no treatment (N=5). Subjects completed three hours of moderate intensity dance in the afternoons, and one to two hours of easy dance in the evening. Rectus femoris, hamstring, and gastrocnemius flexibility, thigh circumference in three areas, vertical jump, and PMS were measured before the morning session, before treatment, and after the afternoon session. Agility and anaerobic capacity tests were performed prior to the morning workouts on the first and fourth training days. No significant differences (p> 0.05) were observed between groups over time in flexibility, vertical jump, agility, anaerobic capacity, fatigue, or PMS. Significant differences (p < 0.05) were observed in mid-thigh circumference over time, specifically during day 2 of training. A non-significant trend (p> 0.05) towards smaller mid-thigh circumference over time in the CWI group was also observed. A trend towards increased gastrocnemius flexibility from baseline to 72 hr post was observed in the CWI treatment (BL: 12.40 + 1.90 degrees; 72 hr post: 13.20 + 2.61 degrees, p > 0.05, d =0.35), while a decrease in flexibility was observed in the control treatment (BL: 15.57 + 1.61 degrees, 72 hr post: 13.14 + 2.21 degrees, p > 0.05, d =1.26). CWI, did not enhance subsequent performance or recovery or attenuate perceived muscle soreness over 3 days in untrained competitive female dancers. Effect size indicates that the results may be limited by the small sample size in each group. |
