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Purpose: To examine the effects of one 30-min (C-30), two 15-min (I-15), and three 10-min (I-10) exercise sessions on excess postexercise oxygen consumption (EPOC), substrate utilization, and resting metabolic rate. Methods: Nineteen young women undertook treadmill walking at 70% VO2max, followed immediately by a 20-min EPOC measurement. Blood was collected preexercise, immediately postexercise, and at 20 min postexercise and was analyzed for lactate, glucose, free fatty acids, epinephrine, and norepinephrine concentrations. Resting metabolic rate was measured the morning of and the morning after each exercise condition. Results: Total exercise energy expenditure did not differ between the three conditions. There were no significant differences among conditions for individual EPOC; however, the cumulative EPOC from I-15 (3,247 +/- 1,327 mL O2) and I-10 (4,060 +/- 1,055 mL O2) were greater than those from C-30 (1,848 +/- 1,586 mL O2). Lactate and glucose were not different among conditions, but free fatty acids were significantly higher immediately postexercise in C-30 (186.8 +/- 91.7 mg x L-1) compared to I-10 (100.4 +/- 64.1 mg x L-1) and I-15 (120.2 +/- 69.1 mg x L-1). Norepinephrine was increased immediately postexercise in all three conditions, and these values differed from preexercise and 20-min postexercise values. No changes were observed in resting metabolic rate. Conclusion: These findings suggest that intermittent exercise compared to continuous exercise may increase the total amount of energy expended during recovery from exercise when exercise is performed at 70% of VO2max. [ABSTRACT FROM AUTHOR]

We examined the effects of sodium bicarbonate ingestion on the VO2 slow component during constant-load exercise. Twelve physically active males performed two 30-min cycling trials at an intensity above the lactate threshold. Subjects ingested either sodium bicarbonate (BIC) or placebo (PLC) in a randomized, counterbalanced order. Arterialized capillary blood samples were analyzed for pH, bicarbonate concentration ([HCO3-]), and lactate concentration ([La]). Expired gas samples were analyzed for oxygen consumption (VO2). The VO2 slow component was defined as the change in VO2 from Minutes 3 and 4 to Minutes 28 and 29. Values for pH and [HCO3-] were significantly higher for BIC compared to PLC. There was no significant difference in [La] between conditions. For both conditions there was a significant time effect for VO2 during exercise; however, no significant difference was observed between BIC and PLC. While extracellular acid-base measures were altered during the BIC trial, sodium bicarbonate ingestion did not attenuate the VO2 slow component during constant-load exercise. [ABSTRACT FROM AUTHOR]

Objective: To determine if 35 days of creatine supplementation (Cr) followed by 28 days of no supplementation altered lower leg anterior compartment pressure (ACP) at rest and after exercise.Design and Setting: Subjects were divided into 2 treatment groups: (1) high dose (0.3 g Cr x kg body mass[-1] x d[-1] for 7 days followed by 0.03 g Cr x kg body mass[-1] x d[-1] for 28 days), or (2) low dose (0.03 g Cr x kg body mass[-1] x d[-1] for 35 days). After 35 days, supplementation was terminated, and no Cr was ingested for 28 days.Subjects: Sixteen physically active, healthy, college-aged males (VO2max = 47.6 +/- 5.1 mL x kg[-l x min[-1]).Measurements: At baseline, 7 days and 35 days of supplementation, and 28 days postsupplementation, ACP was measured preexercise and immediately, 1, 5, 10, and 15 minutes postexercise after a treadmill run at 80% VO2max.Results: For ACP, there was no significant group-by-time interaction, but there was a significant time effect for group when the data were combined. ACP was significantly increased at preexercise, immediately postexercise, and 1, 5, and 10 minutes from baseline to 7 days. ACP remained significantly elevated from baseline at 35 days immediately postexercise and 1 minute postexercise. After 28 days of no supplementation, ACP began to return to presupplementation levels, with only the 1-minute postexercise measurement significantly elevated from baseline.Conclusions: Creatine supplementation increased ACP at rest and after exercise, and ACP began to return to normal after 28 days of no supplementation. [ABSTRACT FROM AUTHOR]

Objective: To report abnormal changes in lower leg anterior compartment pressure in 1 subject who consumed creatine as a dietary supplement.Background: The subject received creatine at a dosage of 0.3 g x kg body mass-1 x d-1 for 6 days, followed by 0.03 g x kg body mass-1 x d-1 for 28 days. Thereafter, the subject consumed no supplement for 21 days. Compartment pressure was measured pre-exercise and for 15 minutes postexercise after a treadmill run for 20 minutes at 80% of VO[2] max before supplementation and after 6 and 34 days of supplementation.Differential Diagnosis: Normally, resting anterior compartment pressure is less than 15 mm Hg, whereas postexercise pressure is below 30 to 35 mm Hg. Creatine supplementation for 6 days dramatically increased pressure at rest (31 mm Hg) and at 1 minute (67 mm Hg), 5 minutes (35 mm Hg), 10 minutes (28 mm Hg), and 15 minutes (26 mm Hg) postexercise. Pressure remained high at rest (35 mm Hg) and at 1 minute (109 mm Hg), 5 minutes (90 mm Hg), 10 minutes (87 mm Hg), and 15 minutes (69 mm Hg) postexercise after 34 days of supplementation.Treatment: The subject stopped taking creatine for 21 days. Compartment pressure was measured at rest and after exercise after 7 and 21 days with no supplementation. Anterior compartment pressure decreased after cessation of creatine supplementation. However, pressures were elevated at 7 days postsupplementation at rest (26 mm Hg) and at 1 minute (112 mm Hg), 5 minutes (58 mm Hg), 10 minutes (40 mm Hg), and 15 minutes (30 mm Hg) postexercise. Pressures at 21 days postsupplementation remained high at rest (24 mm Hg) and at 1 minute (64 mm Hg), 5 minutes (42 mm Hg), 10 minutes (27 mm Hg), and 15 minutes (27 mm Hg) postexercise.Conclusion: These data indicate that creatine supplementation can substantially increase anterior compartment pressure in the leg. [ABSTRACT FROM AUTHOR]

This investigation examined using heart rate (HR), central rating of perceived exertion (C-RPE) and peripheral rating of perceived exertion (P-RPE) values obtained during a graded exercise test (GXT) for monitoring intensity during a 5000 m field run. Ten trained runners performed a GXT to determine HR, C-RPE and P-RPE values at a blood lactate concentration ([La]) >/=4.0 mM. Three randomly assigned 5000 m runs were performed on an outdoor track using the HR, C-RPE and P-RPE values from the GXT. [La] was assessed at 1000 m, 3000 m and 5000 m and running velocity (RV) at each 1000 m interval. No significant interaction effect was observed for [La] or RV among trials. A significant time effect was found among trials for [La] and RV. The 5000 m [La] was significantly different from the GXT for the C-RPE and P-RPE trials, but not the HR trial. The 1000 m RV for each trial was significantly different from the RV of the GXT. The 2000 m and 5000 m RV for P-RPE were significantly different from the RV of the GXT. The data indicate that using HR values from a GXT were better than using RPE values for maintaining exercise intensity at a [La] of 4.0 mM during a 5000 m field run in trained runners. [ABSTRACT FROM AUTHOR]

This study compared ventilatory and metabolic responses during exercise using three breathing assemblies: mouthpiece/noseclip (BV); mouth/face mask (MM); and facemask (FM). Ten male runners completed three maximal treadmill tests with breathing assembly randomly assigned. Metabolic and ventilatory data were recorded every 15s, and heart rate (HR) and rating of perceived exertion (RPE) each min. No significant differences were found for treadmill run time, HR(max), respiratory exchange ratio (RER), and RPE, indicating similar efforts on all trials. No significant differences were found at maximal exercise for VO(2), minute ventilation (V[E]), tidal volume (V[T]), and breathing frequency (f). At ventilatory threshold (T[VENT]), VO(2), V(E), and f were not significantly different. However, peak flow (PF) was significantly higher for BV than FM, and V(T) was significantly higher for BV than MM and FM. Results indicate alterations in ventilatory mechanics occur at T(VENT), but type of breathing assembly does not significantly affect maximal values. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine how fat mass affects the maximal fat oxidation rates of women. Fourteen active, healthy women (age, 21-31 years) with body composition ranging from 18.6 to 30.0% fat were divided into 2 groups (15-24.9% = lower-fat group; 25-35% = higher-fat group). On day 1, subjects performed a graded exercise test on the treadmill to determine maximal oxygen consumption (VO2max). On day 2, subjects were measured for % fat and performed a maximal fat oxidation test. Fat and carbohydrate oxidation rates were determined using gas exchange analysis. Fat oxidation in absolute (in gram per minute) and relative to fat-free body mass (in milligram per kilogram of fat-free mass per minute) was determined using stoichiometric equations and appropriate energy equivalents. There were no significant differences (p > 0.05) in maximal fat oxidation rates between the women in lower-fat (0.39 ± 0.10 g·min-1, 8.52 ± 2.69 mg·kg FFM·min-1) and higher-fat (0.49 ± 0.13 g·min-1, 10.81 ± 2.80 mg·kg-1 FFM·min-1) groups. Maximal fat oxidation occurred at an exercise intensity of 55.7 ± 11.1% and 59.1 ± 5.4% VO2max for the lower-fat and higher-fat groups, respectively, with no significant difference between groups (p > 0.05). The maximal fat oxidation rate (g·min-1 and mg·kg-1 FFM·min-1) was not significantly correlated with any of the descriptive variables (fat mass, fat-free mass, percent body fat, or VO2max). In conclusion, personal trainers and health practitioners can use the exercise intensities that elicited the highest rate of fat oxidation to prescribe exercise programs to women, despite their body composition, that prevent weight gain and/or promote body fat and body weight loss.

Metabolic syndrome (MetSyn) is a clustering of metabolic and cardiovascular disease risk factors. The purpose of this study was to determine the prevalence of MetSyn risk factors in high school (HS) and college (College) football players and to examine if the prevalence varied according to body fat percent (%Fat). One hundred twenty-three males (height 179.0 ± 6.7 cm; weight 89.4 ± 19.6 kg) from 7 different high schools and 82 males (height 186.2 ± 6.8 cm; weight 99.6 ± 16.8 kg) from one university participated. All testing occurred in the early morning after an overnight fast. %Fat, waist circumference, resting systolic and diastolic blood pressure, fasting triglyceride, high-density lipoprotein (HDL) cholesterol, and blood glucose were determined using standard testing procedures. The MetSyn risk factor levels were determined using American Heart Association criteria. Subjects were grouped by position and playing level (HS, College). Independent t-tests, chi-square analysis, 2-way analysis of variance, and path analytic models were used in the statistical analysis. Significance was set at p < 0.05. 6.8% (n = 14) of the sample met the American Heart Association criteria for MetSyn. Offensive and defensive linemen accounted for 92.3% of the players meeting MetSyn criteria with each playing level (HS, College) having 7 subjects. The MetSyn criteria differed significantly across %Fat. Obese players were more likely to meet the criteria for MetSyn. %Fat was a statistically significant predictor of mean arterial blood pressure, HDL cholesterol, and waist circumference. The MetSyn exists in both HS- and College-level football players, with almost all cases occurring in the athletes with the highest levels of %Fat (offensive/defensive lineman). Strength and conditioning coaches should be aware of the prevalence of MetSyn risk factors in offensive and defensive linemen and take appropriate actions to ensure athlete safety.

We examined the effects of consuming a 6% carbohydrate (CHO) beverage during exercise on substrate oxidation in active, young Caucasian women with higher body fat (HF) (>25%) and lower body fat (LF) (<25%). The HF group (n = 9) had 32.4% ± 5.6% fat and the LF group (n = 8) had 20.0% ± 3.0% fat. Subjects completed 2 sessions of 45 min of treadmill exercise at 55% of maximal oxygen consumption. Immediately prior to and at 15-min intervals during exercise, subjects consumed 25% of a total volume of a CHO beverage (1 g CHO·kg(-1)) or a placebo (PLC). During exercise and for 2 h after exercise, expired gases were analyzed to determine oxidation rates for CHO (CHO-OX) and fat (FAT-OX). During exercise, significant differences (p < 0.05) in CHO-OX (mg·kg fat-free mass(-1)·min(-1)) were found between groups for the CHO trial (LF, 35.4 ± 4.7 vs. HF, 29.8 ± 3.6) and the PLC trial (LF, 33.7 ± 6.4 vs. HF, 26.3 ± 4.3). CHO-OX was significantly higher during the first hour of recovery in both the LF group (CHO, 9.3 ± 2.1 vs. PLC, 5.3 ± 2.4) and the HF group (CHO, 8.7 ± 2.0 vs. PLC, 4.2 ± 1.0), but during the second hour of recovery, only the HF group had a higher CHO-OX (CHO, 5.3 ± 1.8 vs. PLC, 3.9 ± 1.1). FAT-OX was significantly lower during the first hour of recovery in both the LF group (CHO, 0.6 ± 0.4 vs. PLC, 1.0 ± 0.4) and the HF group (CHO, 0.4 ± 0.4 vs. PLC, 1.4 ± 0.4), as well as during the second hour of recovery in both the LF group (CHO, 0.8 ± 0.4 vs. PLC, 1.3 ± 0.5) and the HF group (CHO, 0.9 ± 0.6 vs. PLC, 1.6 ± 0). CHO ingestion promotes CHO-OX and suppresses FAT-OX during and following exercise in physically active women with low and high levels of body fat.

The purpose of this study was to document changes in height (cm), body weight (kg), and body composition (%fat) of American football players from 1942 to 2011. Published articles were identified from databases and cross-referencing of bibliographies. Studies selected met the requirements of (1) having 2 of 3 dependent (height, body weight, and body composition) variables reported in the results; (2) containing a skill level of college or professional; (3) providing measured not self-reported data; and (4) published studies in English language journals. The data were categorized into groups based on skill level (college and professional). The player positions were grouped into 3 categories: mixed linemen (offensive and defensive linemen, tight ends, and linebackers), mixed offensive backs (quarterback and running backs), and mixed skilled positions (defensive backs and wide receivers). Linear regression was used to provide slope estimates and 95% confidence intervals (CIs). Unpaired t-tests were used to determine whether an individual regression slope was significantly different from zero. Statistical significance was set at p < 0.017. College level players in all position groups have significantly increased body weight over time (95% CI: mixed lineman 0.338-0.900 kg·y(-1); mixed offensive backs 0.089-0.298 kg·y(-1); mixed skilled 0.078-0.334 kg·y(-1)). The college level mixed linemen showed a significant increase over time for height (95% CI: 0.034-0.188 cm·y(-1)) and body composition (0.046-0.275% fat per year). Significant increases in body weight over time were found for professional level mixed lineman (95% CI: 0.098-0.756 kg·y(-1)) and mixed offensive backs (95% CI: 0.1800-0.545 kg·y(-1)). There were no other significant changes at the professional level. These data demonstrate that body weight of all college players and professional mixed lineman have significantly increased from 1942 to 2011.

The purpose of this study was to compare resistance exercise training (RT) to aerobic exercise training (AE) on the clinical risk factors for metabolic syndrome (MetSyn) in physically inactive overweight males (age 27-48 years). Subjects with at least one risk factor for MetSyn performed RT (n = 13, age 35.1 ± 4.7 years, BMI 31.2 ± 2.7 kg/m(2)) or AE (n = 9, age 37.6 ± 4.9 years, BMI, 31.2 ± 3.2 kg/m(2)) for 6 months. Training frequency and exercise session duration were equal and by 3 months the subjects exercised 4 day/week for 45 min/session. Blood lipids and glucose, waist circumference, and mean arterial blood pressure (MAP) were measured at 0, 3, and 6 months. A MetSyn z score was calculated for each subject from triglycerides, HDL cholesterol, fasting glucose, waist circumference, and MAP. Statistical significance was set at p ≤ 0.05. No significant differences existed between RT and AE groups at 0 month. AE showed a significant reduction in MetSyn z score from 0 (0.91 ± 3.57) to 6 months (-1.35 ± 2.95), while RT approached significance (p = 0.07) from 0 (0.09 ± 2.62) to 6 months (-1.30 ± 2.22). Triglycerides (mmol/L) significantly decreased in AE from 0 (1.93 ± 0.90) to 6 months (1.41 ± 0.70). Waist circumference (cm) significantly decreased in AE from 0 (106.8 ± 7.3) to 6 months (101.2 ± 6.5), and in RT from 0 (108.4 ± 9.0) to 6 months (105.7 ± 7.0). MAP (mmHg) decreased in RT from 0 (93.8 ± 5.8) to 6 months (87.5 ± 6.1) and in AE from 0 (97.6 ± 7.0) to 6 months (91.3 ± 6.8). With equal training frequency and exercise session duration, both RT and AE training, when paired with energy restriction improve the clinical risk factor profile for MetSyn.

We compared the effects of consuming a 2-day low-carbohydrate (CHO) diet (low-CHO; 20% CHO, 40% protein, 40% fat) versus an isocaloric 2-day moderate-CHO diet (mod-CHO; 55% CHO, 15% protein, 30% fat) on substrate oxidation during and after exercise in ten active, young women. Subjects were 24.9 ± 6.2% body fat with a VO(2max) of 68.8 ± 13.8 ml/kg FFM/min. For 2 days prior to exercise, subjects consumed either the mod-CHO or the low-CHO diet and then completed treadmill exercise at 55% of VO(2max) until 350 kcal of energy was expended. During exercise and for 2 h post-exercise, expired gases were analyzed to determine oxidation rates for CHO (CHO-OX) and fat (FAT-OX). Significant differences (p < 0.05) were found between diets for CHO-OX and FAT-OX (mg/kg FFM/min) during exercise, 1 h post-ex, and 2 h post-ex. During exercise, FAT-OX was higher (low-CHO 8.7 ± 2.2 vs. mod-CHO 6.2 ± 2.2) and CHO-OX was lower (low-CHO 25.1 ± 5.6 vs. mod-CHO 31.1 ± 6.2) following the low-CHO diet. A similar trend was observed during 1 h post-ex for FAT-OX (low-CHO 2.2 ± 0.5 vs. mod-CHO 1.6 ± 0.5) and CHO-OX (low-CHO 2.5 ± 1.2 vs. mod-CHO 4.1 ± 1.9), as well as 2 h post-ex for FAT-OX (low-CHO vs. 1.9 ± 0.5 mod-CHO 1.7 ± 0.4) and CHO-OX (low-CHO 2.5 ± 0.9 vs. mod-CHO 3.1 ± 1.1). Significant positive correlations were observed between VO(2max) and CHO-OX during exercise and post-exercise, as well as significant negative correlations between VO(2max) and FAT-OX post-exercise in the low-CHO condition. Waist circumference and FAT-OX exhibited a significant negative correlation during exercise in the low-CHO condition. Dietary macronutrient intake influenced substrate oxidation in active young women during and after moderate intensity exercise.

The purpose of this study was to examine relationships between laboratory tests and on-ice skating performance in division I men's hockey athletes. Twenty-one men (age 20.7 +/- 1.6 years) were assessed for body composition, isokinetic force production in the quadriceps and hamstring muscles, and anaerobic muscle power via the Wingate 30-second cycle ergometer test. Air displacement plethysmography was used to determine % body fat (%FAT), fat-free mass (FFM), and fat mass. Peak torque and total work during 10 maximal effort repetitions at 120 degrees .s were measured during concentric muscle actions using an isokinetic dynamometer. Muscle power was measured using a Monark cycle ergometer with resistance set at 7.5% of body mass. On-ice skating performance was measured during 6 timed 89-m sprints with subjects wearing full hockey equipment. First length skate (FLS) was 54 m, and total length skate (TLS) was 89 m with fastest and average skating times used in the analysis. Correlation coefficients were used to determine relationships between laboratory testing and on-ice performance. Subjects had a body mass of 88.8 +/- 7.8 kg and %FAT of 11.9 +/- 4.6. First length skate-Average and TLS-Average skating times were moderately correlated to %FAT ([r = 0.53; p = 0.013] and [r = 0.57; p = 0.007]) such that a greater %FAT was related to slower skating speeds. First length skate-Fastest was correlated to Wingate percent fatigue index (r = -0.48; p = 0.027) and FLS-Average was correlated to Wingate peak power per kilogram body mass (r = -0.43; p = 0.05). Laboratory testing of select variables can predict skating performance in ice hockey athletes. This information can be used to develop targeted and effective strength and conditioning programs that will improve on-ice skating speed.

The purpose of the current investigation was to identify any existing relationships between off-ice performance measures and on-ice performance quantified by speed and acceleration. Twenty-seven women (age 19 +/- 1 year; body mass (59.5 +/- 6.8 kg; height 164.6 +/- 6.35 cm; body fat 23.2 +/- 3.9%) who were collegiate synchronized figure skaters volunteered for the investigation. To examine the relationship between off-ice performance and on-ice speed and acceleration, collegiate synchronized skaters were evaluated on various performance tests over a 1-week period. Off-ice tests completed were peak torque for hip abduction and adduction, 40-yard sprint, vertical jump height, 30-second slide board stride count, and a 1-RM (repetition maximum) squat. On-ice tests included a timed single lap sprint, 4.5-minute (duration of long program) lap count, and an approximately 16.5-m (18-yard blue line to blue line) timed acceleration. Significance was set at P < or = 0.05. This study showed 3 primary findings: (a) slide board stride count was the single best predictor for both single lap on-ice speed and acceleration accounting for 53.5% (adjusted R2 value) of the variance in the single lap test and 42.5% (adjusted R2 value) of the variance in acceleration times; (b) vertical jump height test was the second best predictor for both the single lap test and on-ice acceleration accounting for 36.6% and 39.9% (adjusted R2 values) of the variance in times recorded, respectively; and (c) the best combined predictors for the single lap speed test were slide board stride count and 40-yard dash (R2 = 0.675), whereas the best combined predictors for on-ice acceleration were slide board stride count and vertical jump height test (R2 = 0.571). Conditioning for synchronized skaters to enhance performance of on-the-ice speed and acceleration should include slide board training implementation of plyometric and linear speed training while developing and maintaining 1-RM strength to support power capabilities.

High-intensity (HI) resistance exercise augments postexercise glucose uptake to a greater degree than low-intensity (LO) resistance exercise; however, few studies have equated the work volumes between intensity levels. The purpose of this study was to compare the effect of acute HI and LO resistance exercise of equal work volume on glucose uptake in resistant-trained men. Fifteen healthy male (22.9 +/- 3.8 years old), resistance-trained (6.7 +/- 3.9 years) subjects completed three treatment sessions: CON (no-exercise control), HI (3 x 8, 85% 10-RM), and LO (3 x 15, 45% 10-RM). HI and LO sessions consisted of eight exercises. Glucose uptake was measured the following morning by using the hyperinsulinemic euglycemic clamp technique. Glucose disposal was measured by analyzing the glucose infusion rate during the final 30 minutes of steady-state blood glucose concentrations. Insulin sensitivity was calculated by dividing the glucose infusion rate by the average insulin infusion. Results indicate that fasting blood glucose levels were not significantly different among treatment sessions (CON = 80.5 +/- 5.3 versus HI = 77.0 +/- 4.9 versus LO = 77.1 +/- 6.0 mg.dL). Glucose uptake was not significantly different among treatment sessions (CON = 11.3 +/- 3.0 versus HI = 11.7 +/- 2.7 versus LO = 11.4 +/- 2.8 mg.kg FFM.min). Insulin sensitivity did not change among treatment sessions (CON = 0.26 +/- 0.09 versus HI = 0.28 +/- 0.07 versus LO = 0.27 +/- 0.06 (mg.kg FFM.min)/(uU.mL)). The data indicate that the resistance training sessions did not modify acute insulin sensitivity. This may have been because of the high levels of fitness of the subjects, which allowed for the cellular adaptations for enhanced insulin sensitivity and glucose uptake that are unaffected by this volume of acute exercise.

Purpose: To determine whether 16 months of moderate-intensity exercise training changes resting metabolic rate (RMR) and substrate oxidation in overweight young adults., Methods: Participants were randomly assigned to nonexercise control (CON, 18 women, 15 men) or exercise (EX, 25 women, 16 men) groups. EX performed supervised and verified exercise 3-5 d/wk, 20-45 min/session, at 60-75% of heart-rate reserve. Body mass and composition, maximal oxygen consumption (VO2max), RMR, and resting substrate oxidation were assessed at baseline and after 9 and 16 months of training., Results: EX men had significant decreases from baseline to 9 months in body mass (94.6+/-12.4 to 89.2+/-9.5 kg) and percent fat (28.3+/-4.6 to 24.5+/-3.9). CON women had significant increases in body mass (80.2+/-8.1 to 83.2+/-9.2 kg) from baseline to 16 months. VO2max increased significantly from baseline to 9 months in the EX men (3.67+/-0.62 to 4.34+/-0.58 L/min) and EX women (2.53+/-0.32 to 3.03+/-0.42 L/min). RMR increased from baseline to 9 months in EX women (1,583+/-221 to 1,692+/-230 kcal/d) and EX men (1,995+/-184 to 2,025+/-209 kcal/d). There were no significant differences within genders for either EX or CON in fat or carbohydrate oxidation. Fat oxidation was significantly higher for women than for men at 9 months in both CON and EX groups., Conclusions: Regular moderate-intensity exercise in healthy, previously sedentary overweight and obese adults increases RMR but does not alter resting substrate oxidation. Women tend to have higher RMR and greater fat oxidation, when expressed per kilogram fat-free mass, than men.

Purpose: To determine whether ethnicity influences postprandial lipemia after a bout of aerobic exercise., Methods: Randomized crossover design. Healthy White (W; n=6) and African American (AA; n=6) women (age, W 27.0+/-3.3 yr, AA 21.6+/-1.4 yr; body-mass index, W 25.0+/-0.93 kg/m2, AA 25.8+/-0.79 kg/m2) participated in 2 treatments (control and exercise), each conducted over 2 d. On d 1, participants rested (control) or walked at 60% of maximal oxygen uptake for 90 min (exercise) and then consumed a meal. On d 2, after a 12-hr overnight fast, participants consumed an oral fat-tolerance test (OFTT) meal of 1.7 g fat, 1.65 g carbohydrate, and 0.25 g protein per kg fat-free mass. Blood was collected pre-meal and at 0.5, 1, 2, 3, 4, 5, and 6 hr post-OFTT and analyzed for triacylglycerol (TAG), glucose, and insulin. Areas under the curve (AUCs) were calculated for each blood variable., Results: A significantly lower TAG AUC was observed for AA (0.86+/-0.24 mmol x L(-1) x 6 hr(-1)) after exercise than for W (2.25+/- .50 mmol x L(-1) x 6 hr(-1)). Insulin AUC was significantly higher for AA after exercise (366.2+/-19.9 mmol x L(-1) x 6 hr(-1)) than for the control (248.1+/-29.2 mmol x L(-1) x 6 hr(-1))., Conclusions: The data indicate that exercise performed approximately 13 hr before an OFTT significantly reduces postprandial lipemia in AA compared with W. It appears that AA women have an increased ability to dispose of TAG after exercise and a high-fat meal.

The purposes of this study are to examine gender differences in the contribution of the arm swing to jump height in men and women basketball players and to examine the role of upper-body strength in the contribution of arm swing to jump height. National Collegiate Athletic Association Division I basketball players (men n = 13, women n = 12) performed 4 jumping movements: squat jumps with hands on hips (SNA) and with arm swings (SA) and countermovement jumps with hands on hips and with arm swings (CMA). Differences were found between the jump heights of men and women. Use of the arms increased the jump height of men more than women. Compared with the SNA, the SA allowed an increase of 7 cm (23%) for men and 4 cm (17%) for women. The CMA allowed for an increase of 10 cm (30%) for men and 6 cm (24%) for women. General upper-body strength measures did not correlate strongly with the effect of arms on jumping, but peak power did. As in previous studies, peak power had a high correlation with jumping performance. These results show that the arm swing contributes significantly to jump performance in both men and women basketball players and that strength training for jumping should focus on power production and lifting exercises that are jump specific.

Introduction: Resistance exercise has been shown to reduce postprandial lipemia, but no dose-response effect has been established., Purpose: The purpose of this study was to determine whether prior resistance exercise exhibited a dose-response effect on postprandial lipemia, while controlling for energy balance., Methods: Subjects were healthy resistance-trained men (n = 4) and women (n = 6) aged 23.4 +/- 2.5 years. Subjects participated in 4 different treatment conditions consisting of control (no exercise), 1 set, 3 sets, and 5 sets of 8 resistance exercises in a repeated-measures design. On day 1, each exercise was performed at 75% of the subject's 1-repetition maximum for 10 repetitions. This was followed by consumption of a postexercise meal equal in caloric volume designed to maintain energy balance. On day 2, after a 12-hour overnight fast (approximately 13 hours postexercise) in the General Clinical Research Center, subjects consumed a high-fat meal consisting of 1.7 g fat, 1.65 g carbohydrate, 0.25 g-protein per kilogram of fat-free mass and equal to 95 kJ of energy per kilogram of fat-free mass. Blood collections occurred before meal, and at 0.5, 1, 2, 3, 4, 5, and 6 hours after meal consumption and were analyzed for triacylglycerol (TAG), glucose, and insulin concentrations. The lipemic response was evaluated as the area under curve (AUC) for TAG versus time. Glucose and insulin AUCs were also calculated., Results: No significant differences were observed among treatments for postprandial lipemia (mmol/L per 6 hours) as measured by the TAG AUC (control 2.96 +/- 0.79, 1 set 2.52 +/- 0.60, 3 sets 2.61 +/- 0.59, 5 sets 2.45 +/- 0.58). Similarly, no differences were observed for insulin or glucose AUC or for insulin sensitivity between treatments. There was a sex effect with TAG AUC significantly lower in women for control, 1 set, and 3 sets. Conclusion The results of this investigation suggest no dose-response attenuation of the postprandial lipemic response to a high-fat meal after previous resistance exercise.

Aim: The classical maximal lactate steady state (MLSS) assessment protocol takes multiple days to measure thus necessitates athletes to return to a laboratory for several visits. The purpose of this study was to assess the validity and reliability of a new protocol (Palmer protocol), which proposes to measure MLSS in a single-day., Methods: Nine endurance-trained males (age 21.1 +/- 1.6 years, VO2max of 63.2 +/- 3.2 ml x kg(-1) x min(-1)) performed the Palmer protocol and the classical MLSS assessment protocol. The classical MLSS protocol consisted of several constant-velocity runs of increasing intensity. The MLSS was defined as the highest velocity associated with an increase in blood lactate concentration ([La-]) = or < 1.0 mmol x L (-1) during the final 20 min of a 30 min run. Concurrent validity was assessed by calculating a Pearson product correlation coefficient between the running velocity at MLSS from the classical protocol and from the single-day Palmer protocol. Test-retest reliability was assessed by calculating a Pearson product correlation coefficient between the running velocities from 2 separate trials of the single-day Palmer protocol., Results: The velocity at MLSS from the single-day Palmer protocol (236.4 +/- 27.8 m x min(-1)) produced a strong correlation of 0.97 (p<0.001) with the velocity at MLSS from the classical protocol (226.3 +/- 22.6 m x min(-1)). An equally strong correlation was calculated from test-retest reliability of the single-day Palmer protocol (r=0.97), (p<0.001)., Conclusion: These results suggest that the single-day Palmer protocol is valid and reliable in the estimation of MLSS.

The effect of consuming meals of different macronutrient content on substrate oxidation following resistance exercise was examined in 9 resistance-trained men (26.2 +/- 2.4 years). Subjects completed 3 resistance exercise bouts of 8 exercises and 1 warm-up set (50% of 10 repetition maximum [RM]), which were followed by 3 sets of 10 repetitions (72.7 +/- 1.9% 10RM), with 60 seconds of rest between sets. Forty-five minutes after exercise, subjects consumed meals of high fat (HF, 37% carbohydrate, 18% protein, and 45% fat), high carbohydrate (HC, 79% carbohydrate, 20% protein, and 1% fat), or water (CON). Fat and carbohydrate oxidation were determined at 15-minute periods after meal consumption for 165 minutes. Blood was collected at preexercise (pre), premeal (0 minutes), and 15, 30, 45, 60, 90, 120, 150, and 180 minutes postmeal and was analyzed for insulin, glucose, triacylglycerols, and glycerol. There were no significant differences among the meal conditions for fat and carbohydrate oxidation. Insulin and glucose concentrations were significantly higher (p < 0.05) following HC at 15, 30, 45, 60, and 90 minutes compared to HF and CON. Triacylglycerol concentrations were significantly higher (p < 0.05) following HF at 90, 120, 150, and 180 minutes compared to HC and CON. Fat and carbohydrate oxidation were not affected by differences in macronutrient meal consumption after an acute bout of resistance training. Different macronutrient consumption does influence insulin, glucose, and triacylglycerol concentrations after resistance exercise.

We examined the effects of liquid carbohydrate (CHO) supplementation on markers of anabolism following high-intensity resistance exercise. Nine resistance-trained men consumed either CHO or placebo (PLC) 10 minutes before and immediately following 2 resistance exercise sessions. Cortisol (CORT), insulin (INS), ammonia (AMM), and glucose (GLU) were measured before, immediately after, and 1.5 and 4 hours after exercise. Urinary nitrogen (NH(+3)) was measured 24 hours before and after exercise. There was a significant difference in INS levels immediately after exercise and 1.5 hours after exercise. No significant differences were observed for CORT, AMM, GLU, or NH(+3)between treatments. Significant within-group differences were found for the PLC group: CORT before compared with immediately after exercise; INS before compared with immediately after exercise and before compared with 1.5 hours after exercise; and AMM before compared with immediately after exercise and before compared with 1.5 hours after exercise. Significant within-group differences were found for the CHO group: CORT immediately after compared with 1.5 hours after exercise and immediately after compared with 4 hours after exercise; INS before compared with 1.5 hours after exercise; and AMM before compared with immediately after exercise. Liquid CHO ingestion leads to a more favorable anabolic environment immediately following a resistance exercise bout; however, our indirect measures of protein degradation were not altered by CHO ingestion.

The effect of carbohydrate supplementation (CHO) on interleukin 2 (IL-2) and interleukin 5 (IL-5) secretion following acute resistance exercise was examined in 9 resistance-trained males. Subjects completed a randomized, double-blind protocol with exercise separated by 14 days. The exercise consisted of a high-intensity, short rest interval squat workout. Subjects consumed 1.0 g x kg body mass(-1) CHO or an equal volume of placebo (PLC) 10 min prior to and 10 min following exercise. Blood was collected at rest (REST), immediately post exercise (POST), and at 1.5 h of recovery (1.5 h POST). Isolated peripheral blood mononuclear cells were stimulated with PHA and assayed for IL-2 and IL-5 secretion. IL-2 secretion was significantly decreased at POST for both the PLC and CHO groups. However, the degree of decrease was less in the CHO group (16%) than in the PLC group (48%), and this difference was statistically significant. These responses were transient, and the values returned to normal by 1.5 h POST. A mild and transient but significant decrease in IL-5 secretion by the PLC group was observed at POST (26%) compared to REST. No significant decrease was observed in IL-5 secretion for CHO from REST to POST (12%). These data support a possible effect of carbohydrate supplementation on IL-2 and IL-5 secretion following high-intensity resistance exercise.

We examined the effects of 2 plyometric training programs, equalized for training volume, followed by a 4-week recovery period of no plyometric training on anaerobic power and vertical jump performance. Physically active, college-aged men were randomly assigned to either a 4-week (n = 19, weight = 73.4 +/- 7.5 kg) or a 7-week (n = 19, weight = 80.1 +/- 12.5 kg) program. Vertical jump height, vertical jump power, and anaerobic power via the Margaria staircase test were measured pretraining (PRE), immediately posttraining (POST), and 4 weeks posttraining (POST-4). Vertical jump height decreased in the 4-week group PRE (67.8 +/- 7.9 cm) to POST (65.4 +/- 7.8 cm). Vertical jump height increased from PRE to POST-4 in 4-week (67.8 +/- 7.9 to 69.7 +/- 7.6 cm) and 7-week (64.6 +/- 6.2 to 67.2 +/- 7.6 cm) training programs. Vertical jump power decreased in the 4-week group from PRE (8,660.0 +/- 546.5 W) to POST (8,541.6 +/- 557.4 W) with no change in the 7-week group. Vertical jump power increased PRE to POST-4 in 4-week (8,660.0 +/- 546.5 W to 8,793.6 +/- 541.4 W) and 7-week (8,702.8 +/- 527.4 W to 8,931.5 +/- 537.6 W) training programs. Anaerobic power improved in the 7-week group from PRE (1,121.9 +/- 174.7 W) to POST (1,192.2 +/- 189.1 W) but not the 4-week group. Anaerobic power significantly improved PRE to POST-4 in both groups. There were no significant differences between the 2 training groups. Four-week and 7-week plyometric programs are equally effective for improving vertical jump height, vertical jump power, and anaerobic power when followed by a 4-week recovery period. However, a 4-week program may not be as effective as a 7-week program if the recovery period is not employed.

Powercranks use a specially designed clutch to promote independent pedal work by each leg during cycling. We examined the effects of 6 wk of training on cyclists using Powercranks (n=6) or normal cranks (n=6) on maximal oxygen consumption (VO2max) and anaerobic threshold (AT) during a graded exercise test (GXT), and heart rate (HR), oxygen consumption (VO2), respiratory exchange ration (RER), and gross efficiency (GE) during a 1-hour submaximal ride at a constant load. Subjects trained at 70% of VO2max for 1 h.d(-1), 3 d.wk(-1), for 6 weeks. The GXT and 1-hour submaximal ride were performed using normal cranks pretraining and posttraining. The 1-hour submaximal ride was performed at an intensity equal to approximately 69% of pretraining VO2max with VO2, RER, GE, and HR determined at 15-minute intervals during the ride. No differences were observed between or within groups for VO2max or AT during the GXT. The Powercranks group had significantly higher GE values than the normal cranks group (23.6 +/- 1.3% versus 21.3 +/- 1.7%, and 23.9 +/- 1.4% versus 21.0 +/- 1.9% at 45 and 60 min, respectively), and significantly lower HR at 30, 45, and 60 minutes and VO2 at 45 and 60 minutes during the 1-hour submaximal ride posttraining. It appears that 6 weeks of training with Powercranks induced physiological adaptations that reduced energy expenditure during a 1-hour submaximal ride.

The current study examined the insulin and glucose response during an oral glucose tolerance test (OGTT) in overweight young adults prior to and following exercise training in the Midwest Exercise Trial (MET). Subjects (N = 66) were randomly assigned to non-exercise control (CON; 16 females, 13 males) or exercise (EX; 22 females, 15 males) groups. EX performed supervised and verified exercise on 3 to 5 days per week in 20- to 45-minute sessions at 60% to 75% of heart rate reserve. OGTTs and assessments for body mass, body composition, and maximal oxygen consumption (Vo(2) max) were performed at baseline, and after 9 and 16 months of training. Blood was collected during a 75-g OGTT and analyzed for glucose and insulin concentrations with the total area under the glucose and insulin curves used in the analysis. The EX males had significant decreases from baseline to 9 months in body mass (94.8 +/- 12.5 to 89.2 +/- 9.8 kg) and percent fat (28.3 +/- 4.8 to 24.2 +/- 3.9) with no further changes at 16 months. CON females had significant increases in body mass (78.2 +/- 6.4 to 81.1 +/- 8.1 kg) and percent fat (36.6 +/- 4.2 to 37.8 +/- 4.7) from baseline to 16 months. Vo(2) max increased significantly from baseline to 9 months in the EX males (3.67 +/- 0.62 to 4.36 +/- 0.55 L/min) and EX females (2.53 +/- 0.32 to 2.99 +/- 0.42 L/min). For glucose area under the curve, there were no significant differences between EX or CON across the 16 months of the study. For insulin area under the curve, there was a significant decrease for male EX from baseline to 9 months (12,535 +/- 6,114 to 8,390 +/- 4,231 microU/L/180 min). We conclude that regular exercise in healthy, previously sedentary overweight adult males leads to improvements in Vo(2) max and weight loss and a reduction in the insulin concentration required to dispose of a set glucose load. In females, improvement in Vo(2) max without weight loss does not lead to improvement in insulin sensitivity.

The purpose of this study was to determine the effects of environmental cooling on force production in the quadriceps and hamstring muscles. Ten men (mean +/- SD: age = 21.4 +/- 2.2 years, height = 168.5 +/- 35.9 cm, body mass = 78.0 +/- 6.4 kg) participated in this study. Each subject completed 2 sets of 10 maximal effort repetitions on a Cybex II isokinetic dynamometer at 3.14 rad x s(-1). Between sets, subjects sat in environmental temperatures of 20, 15, 10, or 5 degrees C for 40 minutes. A significant decrease (p

We investigated the effects of carbohydrate ingestion during recovery from high-intensity exercise on subsequent high-intensity exercise in trained cyclists. Aerobic power was determined, and the competitive cyclists (N = 7) were familiarized with the 100-kJ test protocol (100 KJ-TEST). The subjects performed a first 100 KJ-TEST (RIDE-1), ingested 0.7 g.(kg body mass)(-1) of Gatorlode (CHO) or placebo (PLC), rested for 60 minutes, and then performed a second 100 KJ-TEST (RIDE-2). Blood samples taken before (PRE-1) and after (POST-1) RIDE-1 and before (PRE-2) and after (POST-2) RIDE-2 were analyzed for plasma glucose ([glucose]), lactate, and nonesterified fatty acids ([NEFA]). No significant differences (p > 0.05) were observed between treatments in time to complete RIDE-1 (CHO = 270.3 +/- 29.0 seconds; PLC = 269.9 +/- 33.0 seconds) and RIDE-2 (CHO = 271.7 +/- 26.6 seconds; PLC = 275.3 +/- 30.6 seconds). Plasma [glucose] significantly decreased during the 60-minute recovery for PLC. There was an interaction effect for [NEFA] during recovery, with [NEFA] increasing for PLC and decreasing for CHO. Carbohydrate ingestion after maximal exercise does not appear to influence subsequent short-duration maximal effort exercise in competitive cyclists but does alter plasma [glucose] and [NEFA] relative to a PLC condition.

Background: The purpose of this investigation was to examine the effects of carbohydrate (CHO) supplementation on isokinetic leg extension/flexion exercise performance, blood glucose responses, blood free fatty acid (FFA) responses, and blood lactate (La) responses., Methods: Eight resistance trained males (mean+/-SEM, age: 23.7+/-1.3 yrs, height: 180.0+/-3.5 cm, bodymass: 94.9+/-4.9 kg) participated in a randomized, double blind protocol with testing sessions separated by 7-d. Subjects were given CHO or placebo (P) while performing 16 sets of 10 repetitions at 120 degrees x s(-1) on a Cybex isokinetic dynamometer. Performance variables measured were; total work (TW), average work (AW), peak torque (PT) and average torque (AT). Plasma glucose (PG), FFA, and La were measured prior to testing (PRE), after set 8 (MID), and 16 (POST)., Results: Results indicated that the CHO treatment elicited significantly (p<0.05) more TW (CHO: 41.1+/-3.9 kJ; P: 38.1+/-3.9 kJ) and AW (CHO: 2.6+/-0.2 kJ; P: 2.4+/-0.2 kJ). There were no differences (p<0.05) between treatments for PT of the hamstrings (CHO: 91.6+/-6.5 Nm; P: 87.4+/-8.5 Nm) and quadriceps (CHO: 129.7+/-9.5 Nm; P: 123.0+/-10.6 Nm). The AT of the hamstrings (CHO: 77.8+/-5.2 Nm; P: 75.7+/-8.7 Nm) and quadriceps (CHO: 116.9+/-8.9 Nm; P: 110.0+/-8.5 Nm) were not statistically different (p>0.05) between the treatments. PG was significantly higher at the POST blood draw in the CHO treatment. No significant differences (p>0.05) were observed between the treatments for FFA and La concentrations., Conclusions: The data from this investigation indicate that the use of CHO supplementation during isokinetic leg exercise allows for the performance of more work.

The effect of carbohydrate supplementation (CHO) on the lymphocyte response to acute resistance exercise was examined in 10 resistance-trained males. Subjects completed a randomized double-blind protocol with sessions separated by 14 days. The exercise session consisted of a high intensity, short rest interval squat workout. Subjects consumed 1.0 g á kg body mass(-1) CHO or an equal volume of placebo (PLC) 10 min prior to and 10 min following exercise. Blood was collected at rest (REST), immediately post exercise (POST), and at 1.5 hours and 4.0 hours of recovery, and analyzed for plasma glucose, serum cortisol, leukocyte subsets, and phytohemagglutinin (PHA)-stimulated lymphocyte proliferation. A significant Treatment 3 Time effect was observed for lymphocyte proliferation between CHO and PLC, but post hoc analyses revealed no between-treatment differences at any post-exercise time point. Lymphocyte proliferation was significantly depressed below REST at POST (-39.2% for PLC, -25.7% for CHO). Significant fluctuations in leukocyte subset trafficking were observed for both treatments at POST, 1.5 hours, and 4.0 hours. Plasma glucose was significantly increased POST in CHO compared to PLC. Cortisol was significantly increased from REST to POST in both treatments. These data support a minimal effect of carbohydrate ingestion on the lymphocyte response to high-intensity resistance exercise.

The purpose of this investigation was to examine white blood cell counts (WBC), immunoglobulin (IgA, IgG, IgM) levels, and T-cell proliferation following acute resistance training in 9 untrained (UT) and 6 trained (TR) women. Resistance training on 7 Universal machines at the subject's 10 repetition maximum (IORM) was performed at 89 +/- 5% for UT and 88 +/- 3% for TR. Blood was analyzed for WBCs and Ig levels pre-exercise, immediately postexercise, and 1.5, 3, and 24 hours postexercise. T-cell proliferation was determined pre-exercise and 3 hours postexercise through response to phytohemagglutanin (PHA). WBCs were significantly elevated in the UT subjects 1.5 and 3 hours postexercise compared with pre- and immediately postexercise; no differences (p < 0.05) were observed in TR subjects. No significant differences were found for Ig levels either between or within groups, although there was a trend for decreased IgG following exercise. T-cell proliferation was significantly decreased in the UT at 3 hours postexercise (0.27 +/- 0.06 units) compared with pre-exercise (0.41 +/- 0.06 units), whereas the proliferative response in TR was not significantly different from pre-exercise (0.48 +/- 0.04 units) to 3 hours postexercise (0.34 +/- 0.06 units). These data indicate that UT subjects experience an increase in WBC counts and a decrease in T-cell proliferative ability after acute resistance training, whereas TR subjects experience no significant change in these parameters.

The effects of different types of music on ratings of perceived exertion (RPE) during 20 min. of moderate intensity exercise were examined. 27 physically active subjects (age 18-30 yr.) performed a graded exercise test on a cycle ergometer to establish peak aerobic power (VO2peak). Four 20-min. exercise sessions were performed at a power output equal to 70% of VO2peak in a soundproof visually sterile room. The sessions were randomly assigned from the conditions of fast upbeat music, classical music, self-selected music, and no music. Heart rate, peripheral RPE, central RPE, and overall RPE were measured every 5 min. during exercise. No significant differences were found in heart rate among the four conditions indicating similar exercise intensity during each condition. Each type of music resulted in a reduced peripheral, central, and overall RPE when compared with the no-music condition. The data indicate that different types of music can act as an effective passive distractor during exercise and are associated with lower ratings of perceived exertion.

The effects of carbohydrate (CHO) supplementation on muscle glycogen and resistance exercise performance were examined with eight highly resistance trained males (mean +/- SEM, age: 24.3 +/- 1.1 years, height: 171.9 +/- 2.0 cm, body mass: 85.7 +/- 3.5 kg; experience 9.9 +/- 2.0 years). Subjects participated in a randomized, double blind protocol with testing sessions separated by 7 days. Testing consisted of an initial isokinetic leg exercise before and after an isotonic resistance exercise (IRT) session consisting of 3 leg exercises lasting approximately 39 min. Subjects consumed a CHO (1.0 g CHO.kg body mass(-1)) or placebo treatment (PLC), prior to and every 10-min (0.5 g CHO.kg body mass(-1)) during the IRT. Muscle tissue was obtained from the m vastus lateralis after a supine rest (REST) immediately after the initial isokinetic test (POST-ISO) and immediately after the IRT (POST-IRT). The CHO treatment elicited significantly less muscle glycogen degradation from the POST-ISO to POST-IRT (126.9 +/- 6.5 to 109.7 +/- 7.1 mmol.kg wet weight(-1)) compared to PLC (121.4 +/- 8.1 to 88.3 +/- 6. 0 mmol.kg wet weight(-1)). There were no differences in isokinetic performance between the treatments. The results of this investigation indicate that the consumption of a CHO beverage can attenuate the decrease in muscle glycogen associated with isotonic resistance exercise but does not enhance the performance of isokinetic leg exercise.

We investigated the effects of carbohydrate ingestion on glycogen replenishment and subsequent short duration, high intensity exercise performance. During Session 1, aerobic power was determined and each subject (N = 6) was familiarized with the 100-kJ cycling test (100KJ-Test). During the treatment sessions, the subjects performed a 100KJ-Test (Ride-1), then consumed 0.7 g.kg body mass-1 of maltodextrin (CHO) or placebo (PLC), rested 60 min, and then performed a second 100KJ-Test (Ride-2). Muscle tissue was collected before (Pre-1) and after Ride-1 (Post-1), and before (Pre-2) and after Ride-2 (Post-2), and analyzed for glycogen concentration. Both treatments yielded a significant increase in glycogen levels following the 60-min recovery, but there was no difference between treatments. Time to complete the 100KJ-Test increased significantly for PLC, but not for CHO. These data indicate that the decrease in performance during Ride-2 in PLC was not the result of a difference in glycogen concentration.

The purpose of this investigation was to determine if passive visual distraction altered ability to regulate exercise intensity as, assessed by ratings of perceived exertion during a 30-min. treadmill run. 10 trained females (VO2max, 52.7 ml.kg-1.min.-1) performed a graded exercise test on a treadmill to assess maximal aerobic power and rating of perceived exertion, oxygen uptake (VO2), heart rate, and running velocity at the 2.5 mmol.L-1 blood lactate concentration. Subjects then used the target rating of perceived exertion to regulate exercise intensity during a control condition, and two treatment runs with passive visual distractions. During the treatment sessions, the subjects ran on a treadmill while viewing a high-action or a low-action video with no audio. The subjects were allowed to adjust the treadmill speed throughout the run to maintain the target rating of perceived exertion; however, subjects were not allowed to view the speed setting. There were no significant differences in blood lactate concentration among the conditions for the control, low action, high action, or graded exercise test (p < or = .05). No significant differences in VO2 or running velocity were found within or among the 30-min. treatment runs and the graded exercise test. Heart rate at 5 min. of exercise during control (158 +/- 3 b.min.-1), low action (158 +/- 3 b.min.-1), and high action (159 +/- 2 b.min.-1) was significantly lower than the graded exercise test (169 +/- 3 b.min.-1). Based on the data collected, visual passive distraction did not alter regulation of intensity using ratings of perceived exertion during a 30-min. treadmill run.

This study involved examining how splitting a 30-min exercise bout on a cycle ergometer into two equal sessions affects excess postexercise oxygen consumption (EPOC) and resting metabolic rate (RMR). In this study, 10 male volunteers (age = 23+/-3.8) participated in two exercise trials, which were randomly assigned in a counterbalanced design and separated by 40 hr. One trial was 30 min of exercise at 70% VO(2)max (CONT), followed by a 40-min measurement of EPOC. The second trial was divided into two 15-min sessions (SPLIT), separated by 6 hr. A 20-min measurement of EPOC followed each SPLIT session. Results indicated that the combined magnitude of EPOCs from SPLIT (7,410+/-1,851 ml) was significantly greater than that from CONT (5,278+/-1305 ml). Data indicate that dividing a 30-min exercise session in to two parts for these individuals significantly increases magnitude of EPOC but does not affect RMR.

Background: L-glutamine (GLN) may have an ergogenic effect during exercise considering its base generating potential. We attempted to determine whether GLN ingestion influences acid-base balance and improves high intensity exercise performance., Method: Ten trained males performed five exercise bouts on a cycle ergometer at 100% of VO2 peak. The first four bouts were 60 sec in duration, while the fifth bout was continued to fatigue. Each bout was separated by 60 sec of recovery. The exercise bouts were initiated 90 min after ingesting 0.03 g.kg body mass-1 of either GLN or placebo (PLC). Venous blood samples were collected pre-ingestion (PRE-IN), pre-exercise (PRE-EX), and following bouts four (B4) and five (B5) and analyzed for pH, bicarbonate concentration (HCO3), and lactate concentration (La-). Time to fatigue for B5 was used as a performance measure., Results: pH, [HCO3], and [La-] were not significantly different (p > 0.05) between conditions for PRE-IN, PRE-EX, B4, and B5. Time to fatigue was not significantly different between conditions and averaged 263.4 +/- 24.5 sec and 263.2 +/- 19.4 sec for the GLN and PLC trials, respectively., Conclusions: These data indicate that acute ingestion of L-glutamine does not enhance either buffering potential or high intensity exercise performance in trained males.

Thirty physically active healthy men (20.1 +/- 1.6 yr) were randomly assigned to participate for 10 wk in one of the following training groups: endurance trained (ET; 3 days/wk jogging and/or running), resistance trained (RT; 3 days/wk resistance training), or combined endurance and resistance trained (CT). Before and after training, basal metabolic rate (BMR), percent body fat (BF), maximal aerobic power, and one-repetition maximum for bench press and parallel squat were determined for each subject. Urinary urea nitrogen was determined pre-, mid-, and posttraining. BMR increased significantly from pre- to posttraining for RT (7,613 +/- 968 to 8,090 +/- 951 kJ/day) and CT (7,455 +/- 964 to 7,802 +/- 981 kJ/day) but not for ET (7,231 +/- 554 to 7,029 +/- 666 kJ/day). BF for CT (12.2 +/- 3.5 to 8.7 +/- 1.7%) was significantly reduced compared with RT (15.4 +/- 2.7 to 14.0 +/- 2.7%) and ET (11.8 +/- 2.9 to 9.5 +/- 1.7%). Maximal aerobic power increased significantly for ET (13%) but not RT (-0.2%) or CT (7%), whereas the improvements in one-repetition maximum bench press and parallel squat were greater in RT (24 and 23%, respectively) compared with CT (19 and 12%, respectively). Urinary urea nitrogen loss was greater in ET (14.6 +/- 0.9 g/24 h) than in RT (11.7 +/- 1.0 g/24 h) and CT (11.5 +/- 1.0 g/24 h) at the end of 10 wk of training. These data indicate that, although RT alone will increase BMR and muscular strength, and ET alone will increase aerobic power and decrease BF, CT will provide all of these benefits but to a lesser magnitude than RT and ET after 10 wk of training.

The effectiveness of a new water delivery system (the Water-Del) was examined for maintaining euhydration compared to other fluid replacement strategies. Subjects (N = 10) performed three 60-min cycling trials (/50% of VO2max) in an environmental chamber (27 degrees C; RH = 50%). Trials were randomly assigned from Water-Del (metered: 200 ml water every 15 min), ad libitum every 15 min (ad-lib-15), and ad libitum (ad-lib). Total water intake (TWI), changes in plasma volume (delta PV), body weight (delta BW), thirst, skin temperature (Tsk), and heart rate (HR) were measured. A significant difference (p < or = .05) among trials was observed for TWI, with metered (1,200 +/- 0 ml) being greater than ad-lib-15 (358 +/- 48 ml) and ad-lib (522 +/- 106 ml). No significant difference was found for delta PV. A significant difference (p < or = .05) for delta BW was observed with metered (0.28 +/- 0.16 kg) being different than ad-lib-15 (-0.63 +/- 0.12 kg) and ad-lib (-0.34 +/- 0.14 kg). No significant differences (p > .05) were found for thirst, Tsk, or HR. The water-Del provides for greater fluid intake during exercise compared to other replacement strategies.

The purpose of this study was to compare three passive attentional manipulations on ratings of perceived exertion (RPE) during exercise. College subjects (13 men, 11 women) completed four 20-min. periods of cycling at 70% of peak aerobic power. Four stimulus conditions were randomly assigned from auditory (listening to fast upbeat music), visual (viewing high-action videotape of human stunts), auditory/visual (both stimulations), and control (no stimulation). Heart rate, peripheral RPE, central RPE, and over-all RPE were measured at 5-min, intervals. Peripheral RPE was significantly higher for visual at 5 and 20 min. compared with auditory/visual and at 5 min. compared to auditory stimulation. Central RPE was significantly higher for visual stimulation at 5, 10, 15, and 20 min. compared with auditory/visual, at 5, 10, and 20 min compared with auditory, and at 5 min. compared to the control condition. Over-all RPE was significantly higher for visual stimulation at 5, 10, 15, and 20 min. compared with auditory/visual and at 5 and 10 min. compared with auditory stimulation. Passive dissociations using high-action visual images may evoke a strong, emotional response which may heighten awareness of physical sensations.

We examined the effects of sodium bicarbonate (BIC) and sodium citrate (CIT) ingestion on distance running performance. Seven male runners [mean VO2max = 61.7 (SEM 1.7) ml.kg-1.min-1] performed three 30-min treadmill runs at the lactate threshold (LT) each followed by a run to exhaustion at 110% of LT. The runs were double-blind and randomly assigned from BIC (0.3 g.kg body mass-1), CIT (0.5 g.kg body mass-1) and placebo (PLC, wheat flour, 0.5 g.kg body mass-1). Venous blood samples were collected at 5, 15 and 25 min during the run and immediately post-exhaustion (POST-EX) and analysed for pH, and the concentrations of lactate ([la-]b) and bicarbonate ([HCO3-]). Performance was measured as running time to exhaustion at 110% of LT (TIME-EX). The pH was significantly higher (P < or = 0.05) for the BIC and CIT trials during exercise, but not POST-EX compared to PLC. The [la-]b was significantly higher (P < or = 0.05) for the CIT trial compared to PLC during exercise, and for both CIT and BIC compared to PLC at POST-EX. Blood [HCO3-] was significantly higher (P < or = 0.05) during exercise for BIC compared to PLC. TIME-EX was not significantly different among treatments: BIC 287 (SEM 47.4)s; CIT 172.8 (SEM 29.7)s; and PLC 222.3 (SEM 39.7)s. Despite the fact that buffer ingestion produced favourable metabolic conditions during 30 min of high intensity steady-state exercise, a significant improvement in the subsequent maximal exercise run to exhaustion did not occur.

The purpose of this study was to examine the effects of sodium citrate (CIT) ingestion on 30 km cycling performance. Eight trained male cyclists (VO2max = 54.7 +/- 1.7 ml.kg-1.min-1) performed two 30 km cycling time trials. The trials were double blind and randomly assigned from CIT or placebo (PLC), with both dosages at 0.5 g.kg body wt-1. Blood samples were collected from an indwelling catheter at 10 km intervals and analyzed for PO2, PCO2, pH, and lactate concentration ([La]). Power output, heart rate (HR) and RPE were measured at 5 min intervals during the trials, while cycling performance was determined from time to complete the 30 km. A repeated measures ANOVA and dependent t-tests were used to locate differences between the trials. A significant difference (p < or = 0.01) was observed for pH and [La] during the trials with CIT being elevated above PLC throughout the ride. No significant differences (p > 0.01) were observed for any of the other dependent variables. However, power output and HR were slightly elevated during the CIT trial. Performance time was significantly faster (p < or = 0.05) for the CIT trial (3459.6 +/- 97.4 s) compared to the PLC trial (3562.3 +/- 108.5 s). The data indicate that favorable metabolic conditions were obtained following CIT ingestion and these likely contributed to the improvement in cycling performance.