Effect of Height on Power Output During Sprint Stair Running

Anaerobic power can be measured by the Margaria-Kalamen Power test , which requires individuals to sprint up 12 stair-steps while striding three stair-steps (MK3) at a time which is challenging for shorter individuals. PURPOSE: to determine if there is a difference in the power output during the MK3 and a modified test requiring only 2 steps per stride (MK2) in males and females who were shorter than 168 cm (ST) and those who were 168 cm or taller (TL). METHODS: All participants performed 3 tests in random order. A modified Wingate test lasting 5s (WG5) against a resistance equal to 7.5% body mass on electronically braked cycle ergometer (Velotron) was performed as a control trial to determine anaerobic power. All participants also performed the MK3 and the MK2. Participants sprinted six meters on flat ground and then ascended a staircase as fast as possible. Participants took 4 strides to climb 12 stair steps during the MK3. Participants took 4 strides to climb 8 stair steps during the MK2. The time to climb from stair step 3 to 9 during the MK3, and from stair step 2-6 during the MK2, was determined by using the average of two times. One investigator was located at the bottom of the stairs and the other investigator was at the top of the stairs using handheld stopwatches. A 2 (height) x 3 (trial) repeated measures ANOVA was performed to determine significant differences. The criterion reference for significant differences was set at p\u3c0.05. RESULTS: Participants in the ST group were 62.2±10.8 kg, and 161.4±5.6 cm tall, and participants in the TL group were 82.1±7.2 kg, and 175.1±9.0 cm tall. Absolute power (MK3 1499±262 vs 938±190W; MK2 1239±138 vs 802±142W; WG5 1007±103 vs 645±150W) and relative power (MK3 18.2±2.3 vs 15.2±2.8W/kg; MK2 15.1±.8 vs 12.9±1.1W/kg; WG5 12.5±.5 vs 10.3±1.2W/kg) were significantly greater (p\u3c.05) in TL compared to SL in each test. In both TL and ST groups for absolute power and relative power, there were significant differences (p\u3c.05) between all three tests (MK3\u3eMK2\u3eWG5). CONCLUSION: Taller individuals may be able to produce more power, both absolute and relative, than shorter individuals during sprint stair running. Absolute and relative power produced during stair running may be greater than power output during the first 5 s of a Wingate test

Alternative Field Test for Wingate Test of Anaerobic Capacity

The 30-s Wingate Anaerobic Power Test (WAPT) has been the gold standard for assessing an individual’s anaerobic power since its development, but it requires expensive equipment. An alternative test, called the Anaerobic Power Run Test (APRT), has been developed as a simple method to predict anaerobic power. PURPOSE: This study was conducted to determine if there is a relationship between the anaerobic capacity determined by a 30-s WAPT and the time to complete the APRT. Additionally, this study will attempt to predict anaerobic capacity based on the time to complete the APRT. METHODS: Participants (8 females, 4 males) between the ages of 18 and 44 years old (mean ± sd = 23.8 ± 5.4 yrs) were included in the study. The two exercise tests were performed at least 24 hours apart in random order. A 5 min cycling warmup was performed before the WAPT. The WAPT was performed using a resistance set at 7.5% of body mass. A 5 min warmup consisting of calisthenic exercises was performed prior to the APRT. The APRT consisted of running five lengths of a NCAA standard basketball court (28.7 m/length, 143.5 m total) as fast as possible. The time it took to run the first length and all five lengths was recorded. A correlation analysis was performed between run time and peak power, mean power, and anaerobic capacity. The criterion reference for statistical significance was set at p\u3c.05. RESULTS: Mean ± sd for APRT run time (33.6 ± 3.8 s), peak power (803 ± 287 W), mean power (508 ± 170 W), and anaerobic capacity (6.9 ± .9 W/kg) during the WAPT were calculated. Run time was significantly correlated with anaerobic capacity (r = -.838, p\u3c0.001), but not with peak power (r = -.217, p=0.50) or mean power (r = -.334, p=0.29). Peak power was not significantly related (r=.024, p=.94) to run time during the first length (28.7 m) of the APRT. Linear regression generated the following prediction equation: Anaerobic Capacity = (-.1888 x Run Time) +13.2807, p\u3c.001. CONCLUSION: The time to complete the APRT was significantly correlated to anaerobic capacity during a WAPT, but not to peak or mean power. Further, the time required to complete the APRT significantly predicted anaerobic capacity determined from a 30-s Wingate test. The significant correlation is likely due to anaerobic capacity being measured relative to body mass and run time being influenced by body mass. The APRT may be an acceptable and inexpensive alternative test of anaerobic capacity when a Wingate test is not feasible. The current study is limited by a small sample size. Future research should include a running familiarization trial

Effects of Two Intensities of Exercise on Memory, Concentration, Planning, and Reasoning

Active workstations (e.g., desk cycles) have recently gained popularity as a means of reducing sedentary behavior in schools. In addition to physical benefits, teachers who have adopted active classrooms anecdotally report cognitive benefits such as students being more focused during instruction. In contrast, empirical work suggests that concurrent exercise has a negative effect on cognition (Lambourne & Tomporowski, 2010). The purpose of this study was to compare the effects of no exercise (CON), low-intensity exercise (LOW), and moderate-intensity exercise (MOD) on a series of cognitive measures. Young, healthy participants (n=48) were randomly assigned to either CON (sedentary), LOW (25-30% HRR), or MOD (50-55% HRR) groups. Those assigned to LOW and MOD exercised with a DeskCycle to achieve desired HR while those in CON sat passively at the Deskcycle. Four Cambridge Brain Sciences Inc. computerized tests were completed to assess planning, concentration, short-term memory, and reasoning while exercising. A self-paced word pair recall test was also administered during the exercise bout, and long-term recall of the word pairs was assessed 24 hours later. Separate one-way ANOVAs were conducted on each cognition test. A 3 (group) x 2 (test) RM ANCOVA with the amount of time spent during each test as covariates was used to assess immediate and delayed recall of word pairs. Groups did not differ in planning, concentration, short-term memory, or reasoning scores (p’s \u3e .05). In both immediate and delayed memory tests, MOD recalled fewer words than CON when controlling for test time (p=.049), and LOW was not different from either group (p\u3e .05). In the present study, exercise did not show any effect on planning, concentration, reasoning, or short-term memory. While previous research shows long-term memory is improved by exercise before or after learning (Roig, et al., 2013), moderate-intensity exercise that occurs during learning seems to impair long-term memory recall

Aerobic Energy Expenditure Comparisons Between One Traditional and CrossFit-Based Exercise Session

This study sought to compare aerobic energy expenditure, recovery VO2, peak heart rate, and peak VO2 achieved across 45 min of exercise and 15 min of recovery performing both traditional and CrossFit®-based exercise. Thirty healthy, physically active participants of both genders (15 men, 15 women) performed a workout following the guidelines of the American College of Sports Medicine (traditional) and a workout following the CrossFit® method. Each workout consisted of a 5 min warm-up (light aerobic exercise and stretching), resistance exercise (both focused on leg exercises), cardiorespiratory exercise (a treadmill run for the traditional exercise and circuit training for the CrossFit®-based exercise) and 5 min cool-down (walking). The cool-down was followed by 10 min of sitting to record recovery values. During each workout the participants wore a K4b2 Cosmed unit to measure energy expenditure and VO2, and a Polar heart rate monitor to measure heart rate. Each measure was compared using a Dependent t-Test. Energy expenditure (468 ± 116 vs. 431 ± 96 kcal, p\u3c0.001), peak heart rate (189 ± 8 vs. 172 ± 8 bpm, p\u3c0.001), peak VO2 (3.22 ± 0.73 vs. 2.81 ± 0.63 L/min, p\u3c0.001) and average 15 min recovery VO2 (0.89 ± 0.24 vs. 0.78 ± 0.18 L/min, p\u3c0.001) were significantly greater in the CrossFit®-based workout. The present study suggests that CrossFit®-based exercise may result in greater aerobic energy expenditure than traditional exercise

Comparison of Cardiorespiratory Responses during Body Weight-Supported Treadmill and Standard Treadmill Exercise

Treadmills that partially support body weight are increasingly being used in athletic rehabilitation settings. The cardiorespiratory response during this type of exercise has been reported in very few published studies. This study was designed to determine the cardiorespiratory response during three exercise intensities during standard treadmill exercise (ST) and body weight-supported treadmill exercise (BWST). In random order, a total of 10 healthy, 18-44 yr old adults (6 males, 4 females) performed BWST and ST trials. Identical exercise sessions were performed on each treadmill except 25% of body weight was supported during BWST exercise such that each participant carried 75% of true body weight. On each treadmill a two-minute warm up was performed at 2 mph and 0% grade, followed by 6 minutes of exercise at 3% grade at each of the following treadmill velocities: 3 mph, 4.5 mph, and 6 mph. Expired respiratory gases were analyzed each minute. Steady state heart rate, VO2, VCO2 and RER were calculated as the average value during the final three minutes of each 6 min exercise stage. Blood pressure and RPE were recorded during the final minute of each stage. A 2x3 repeated measures ANOVA was used to determine significant differences at the p2 between ST and BWST at 4.5 mph (2.14±.39 v 1.42±.27, p2 was significantly different at each exercise intensity and treadmill (ST v BWST: 16.0±1.1 v 13.6±1.2; 31.2±2.0 v 20.6±2.4; 39.8±1.9 v 25.8±2.9 ml∙kg-1∙min-1, p2 between the ST and BWST at 4.5 mph (2.10±.43 v 1.32±.26 L/min,

Body Weight Support on Anti-Gravity Treadmill Induces Less Physiological Strain While Running

The anti-gravity treadmill developed by AlterG® can be used as an alternative to traditional treadmill running. The AlterG® unloads an individual’s body weight through lower body positive pressure (LBPP) and can support up to 80% of an individual’s body weight. The cardiorespiratory response resulting from a bout of exercise on an AlterG® treadmill may be attenuated compared to similar exercise on a traditional treadmill. PURPOSE: The purpose of this study was to compare the physiological responses of running at 0%, 15%, 30%, and 45% of body weight support (BWS) on the AlterG® to a traditional treadmill. METHODS: Ten healthy, active males (n = 3) and females (n = 7) (mean ± SD; age 23 ± 3 yrs, weight 60 ± 9.4 kg, height 167.6 ± 6.4 cm) completed two separate treadmill sessions in a randomized order. The exercise sessions included running on an AlterG® treadmill at 6 mph and 1% grade with 0%, 15%, 30% and 45% BWS for 8 min each. The other exercise session included running on a traditional treadmill (TT) at 6 mph and 1% grade for 8 min. Oxygen consumption (VO2) and respiratory exchange ratio (RER) were measured every minute through indirect calorimetry. Heart rate (HR) was measured every minute with a heart rate monitor and values were averaged during the last five minutes of each exercise trial. Rating of perceived exertion (RPE) was measured every other minute. Multivariate ANOVA was used for statistical analysis for each dependent variable (p \u3c 0.05). RESULTS: BWS at 15%, 30% and 45% on the AlterG® treadmill significantly reduced VO2 18.5%, 28.3 and 33.7% compared to TT and 0%. Additionally, HR with BWS at 15%, 30% and 45% was significantly reduced 8.9%, 13.1% and 17.9% compared to TT and 0%. RER during 30% and 45% was significantly different (-8.6% and -7.4%) from TT. Perceived exertion during 45% BWS was significantly lower (10-20%) than all protocols. There was no significant difference in VO2 or HR reported between 30% and 45%. 0% BWS displayed no significant difference in VO2 or HR when compared to the traditional treadmill. CONCLUSION: Increasing the percentage of BWS while running on the AlterG® treadmill reduced VO2 and HR compared to TT and 0%. Greater levels of BWS (30% and 45%) resulted in lowered RER and perceived exertion (45% only). The AlterG® treadmill appears to lessen the physiological demands of running compared to a traditional treadmill

The Effects of Niacin and Aerobic Exercise in Postmenopausal Women Glucose, Insulin and C-Peptide Profiles

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Influence of Caloric Expenditure on Postprandial Triglyceride and Glucose Responses Following a High-Carbohydrate Meal

Purpose: To examine the effects of aerobic exercise expending 350 and 700 kcal of energy on postprandial triglyceride (Tg) and glucose responses following a high carbohydrate (CHO) meal. Methods: Non-active individuals (n=9 women/4 men; age=22.8±3.7 yrs; Ht=169±10.4 cm; Wt=75.7± 22.4 kg; BMI=26.1±5.8 kg/m2; VO2 max=34.1±6.9 ml/kg/min) completed three trials in a random order: 1) control trial, 2) single exercise session expending 350 kcal (EX350), and 3) single exercise session expending 700 kcal (EX700). Exercise consisted of treadmill walking at 60% VO2 max until 350 and 700 kcal of energy had been expended. The control session consisted of seated rest. The morning after each experimental session, a fasting (12hr) blood sample was collected followed by consumption of a high-CHO liquid meal (2.44 g/kg of fat free mass (CHO), 0.33 g/kg FFM fat, and 0.56 g/kg FFM protein. Blood was collected again at 1, 2, 3, 4, 5, and 6 hrs post-meal and analyzed for (Tg) and glucose concentrations. The areas under the curve (AUC) were calculated for both (Tg) and glucose concentrations. A repeated measures ANOVA was used to determine statistical significance (p\u3c0.05). Results: Baseline glucose concentrations were not different between trials (p=0.71). Postprandial AUC for glucose concentrations were not different between trials (p=0.38). Baseline Tg concentrations were not altered with exercise (p=.94) of 350 kcal (102.7±77.1 mg/dl) or 700 kcal (112.2±80.6 mg/dl) when compared with rest (115.3±113.9 mg/dl). Postprandial Tg concentrations following rest (937.3± 928.4 mg/dl) were not altered (p=0.37) following exercise of 350 kcal (807.1±605.1 mg/dl) or 700 kcal (867.3±672.6). Conclusion: The glucose and Tg responses following a high-CHO meal were unaffected by a prior exercise session. These results are in contrast to previous investigations that have used high-fat test meals demonstrating that a single bout of exercise reduces the postprandial Tg response. Substantial inter-subject variability was seen in the postprandial Tg responses following exercise ranging from reductions of 27.4% to increments of 17.4%. This study was supported by Texas Woman’s University’s Research Enhancement Program

Cardiorespiratory Responses during Aquatic Treadmill Exercise and Land Treadmill Exercise in Adults with Diabetes

The purpose of this study was to compare the effect of aquatic treadmill (ATM) exercise to land treadmill (LTM) exercise in adults with type 2 diabetes. Five participants with type 2 diabetes (T2D group; 4 females, 1 male; age = 51±6 years; height = 170±7 cm; weight = 96±24 kg; body fat = 31.6±2.2%) and five participants without type 2 diabetes (control group; 4 females, 1 male; age = 51±6 years; height = 170±6 cm; weight = 71±15 kg; body fat = 26.8±4.6%) completed the study. Protocols for both ATM exercise and LTM exercise began at 2 mph with 0% grade and increased by 1 mph after 5 minutes at each stage. Termination occurred after participants completed the protocol or reached 85% of heart rate reserve. Heart rate, absolute and relative VO2, and systolic and diastolic blood pressure were measured at rest and during steady-state exercise at each intensity. Mean arterial pressure (MAP) was calculated. A 2 x 2 x 3 Mixed Factorial ANOVA and Bonferroni post hoc test with a significance level of .0125 were used. There was a significant difference (p2 of the two groups at 4 mph while performing the land treadmill exercise (T2D: 14.1±1.4 ml/kg/min vs. control: 18.4±1.6 ml/kg/min, p2 between participant groups or modes of exercise. Those with type 2 diabetes had an increased MAP versus those without type 2 diabetes while performing the land treadmill exercise at 2 mph (T2D: 93±3 mmHg vs. control: 81±5 mmHg, p2, and MAP respond similarly in both groups during ATM and LTM exercise at most treadmill speeds

Anaerobic Performance in Female Collegiate Wrestlers During Ovulation Versus the Mid-luteal Phase of the Menstrual Cycle: A Pilot Study

Anaerobic performance may vary during different phases of the menstrual cycle. The greatest differences occur between the late-follicular phase (i.e., ovulation) and the mid-luteal phase. Optimal anaerobic performance may be observed during the mid-luteal phase. PURPOSE: To explore differences in upper and lower body anaerobic performance during ovulation versus the mid-luteal phase of the menstrual cycle in collegiate female wrestlers. METHODS: Six female collegiate wrestlers (age = 18.6 ± 0.2 yrs; height = 165.0 ± 0.5 cm; body mass = 79.7 ± 9.6 kg; lean body mass = 45.6 ± 2.8 kg; % body fat = 31.4 ± 6.6%) performed both upper and lower body Wingate tests, each lasting 30 seconds, during the ovulation and the mid-luteal phases of the menstrual cycle. Upper and lower body tests were performed 24 hours apart. Menstrual cycle phases were determined by calendar tracking, reverse estimation of ovulation, and administration of a urinary luteinizing hormone test assessed daily until positive results indicated ovulation. Lower body power was measured using a Velotron cycle ergometer, with a resistance of 0.075 kg/kg applied after a 5-second sprint at a resistance of 1 kg (50 W). Peak power (W) and relative power (W/kg) were measured. Upper body power was measured using a Monark hand ergometer with a 0.045 kg/kg resistance applied after a 5-second sprint at a resistance of 0.5 kg (25 W). Peak power (W) and relative power (W/kg) was calculated using rotation count, weight applied, and distance per rotation. Paired t-tests were used to analyze differences in means during the ovulation vs mid-luteal phases with a significance level of 0.05. RESULTS: There were no significant differences between trials for any variables measured. Lower body peak power (W) was 848.3 ± 126.1W vs 855.0 ± 143.9W. Lower body relative power (W/kg) was 11.8 ± 0.7W/kg vs 11.9 ± 0.8W/kg. Upper body peak power (W) was 162.1 ± 29.6 vs 160.2 ± 13.2W. Upper body relative power (W/kg) was 2.3 ± 0.4W/kg vs 2.2 ± 0.2W/kg. CONCLUSION: There may not be an optimal timing of significantly increased anaerobic performance in regard to menstrual phase in these wrestlers