Dieting has been reported to reduce resting energy expenditure (REE) thereby increasing the prevalence of weight gain after weight loss. Intermittent dieting during a weight loss and exercise program may help minimize these adverse effects. PURPOSE: To examine the efficacy of diet cycling with varying macronutrient diet compositions during an exercise and weight loss program on weight loss, health and fitness. METHODS: 43 overweight and sedentary women (35±8 yr; 89±18 kg; 43±4% fat, 33±6 kg/m²) were assigned to a high carbohydrate (HC, n=23) or high protein (HP, n=20) diet group. During the first 30-days, subjects consumed 1,200 kcals/d for 1-wk followed by ingesting 1,500 kcals/d for 3-wks. Subjects then followed a 2,200 kcals/d maintenance diet for 4-wks before repeating the 30-day diet. Diets were 45:30:25% or 30:45:25% carbohydrate, protein and fat, respectively, for the HC and HP groups, respectively. Subjects also participated in the Curves™ circuit training program 3-d/wk and walked briskly for 30-min 3-d/wk. Body mass, DEXA determined body composition and REE data were at each testing interval. Data were analyzed by MANOVA with repeated measures and presented as means ± SD changes from baseline after 1, 2, 3, 4, and 5 months, respectively. RESULTS: Training and dieting significantly decreased body mass (-2.4±2.2, -3.1±2.7, -4.2±3.3, -4.7±4.0, -5.1±4.5 kg, p=0.001); fat mass (-1.6±1.6, -2.5±1.9, -2.9±2.0, -3.5±2.8, -3.6±3.2 kg, p=0.001); lean tissue mass (-0.6±1.7, -0.7±1.9, -1.2±2.2, -0.9±2.2, -1.2±2.3 kg, p=0.004); and percent body fat (-0.8±1.6, -1.5±1.7, -1.5±1.7, -2.2±2.2, -2.1±2.6%, p<0.001). Absolute REE values modestly decreased over time (-52±168, -94±223, -96±236, -78±210, -80±209 kcal/d, p<0.04) but were not significantly changed when accounting for weight loss (18.0±2.5,17.9±2.3, 17.5±2.3, 17.6±2.2, 18.0±2.1, 18.0±2.2, kcal/d/kg, p=0.87). No significant differences were observed between diet groups. CONCLUSION: Short-term diet cycling during a weight loss and exercise program may be an effective way to promote weight loss without associated reductions in REE. In addition, no significant differences were observed between diets on weight loss when diets were 45:30:25% or 30:45:25% carbohydrate, protein, and fat, respectively.
Supported by Curves International, Inc., Waco, TX
 

Effects of Intermittent Dieting During Resistance Training in Women II: Health Markers
M Mardock, J Kresta, M Byrd, J Oliver, C Baetge, S Simbo, Y Jung, M Koozehchian, D Khanna, B Lockard, R Dalton, H Kim, C Rasmussen, R Kreider. Texas A&M, College Station, TX. Email: [email protected]

Dieting has been reported to reduce resting energy expenditure thereby increasing the prevalence of weight gain after weight loss. Intermittent dieting during a weight loss and exercise program may help minimize these adverse effects. PURPOSE: To examine the efficacy of diet cycling with varying macronutrient diet compositions during an exercise and weight loss program on markers of weight loss, health, and fitness. METHODS: 43 overweight and sedentary women (35±8 yr; 89±18 kg; 43±4% fat, 33±6 kg/m²) were assigned to a high carbohydrate (HC, n=23) or high protein (HP, n=20) diet group. During the first 30-days, subjects consumed 1,200 kcals/d for 1-wk followed by ingesting 1,500 kcals/d for 3-wks. Subjects then followed a 2,200 kcals/d maintenance diet for 4-wks before repeating the 30-day diet. Diets were 45:30:25% or 30:45:25% carbohydrate, protein and fat for the HC and HP groups, respectively. Subjects also participated in the Curves™ circuit training program 3-d/wk and walked briskly for 30-min 3-d/wk. Data were analyzed by MANOVA with repeated measures and are presented as means ± SD changes from baseline after 1, 2, 3, 4, and 5 months, respectively. RESULTS: Training and dieting significantly decreased resting systolic blood pressure (-1.0±8, -2.0±10, -1.5±10, -3.6±9, -3.7±7%, p=0.002), circumference of the waist (-4.1±6, -5.1±5, -5.6±6, -5.9±6, -5.0±7%, p=0.001) and hips (-1.1±4, -1.6±4, -1.7±4, -2.1±5, -2.8±6%, p=0.002), the waist to hip ratio (-2.9±6, -3.5±6, -3.9±6, -3.6±7, -2.1±7%, p=0.05), and serum TG levels (-3.6±38, -9.12±32, -13.6±29, -9.9±28, -10.5±37, p=0.02). Total cholesterol and LDL levels also declined, but these changes were not significantly different. There were no significant changes in resting heart rate, diastolic blood pressure, glucose or HDL levels. No significant differences were observed between diet groups. CONCLUSION: Short-term diet cycling during a weight loss and exercise program may be an effective way to promote changes in waist and hip circumference while markedly reducing TG levels. In addition, no significant differences were observed between diets on health markers when diets were 45:30:25% or 30:45:25% carbohydrate, protein, and fat, respectively.
Supported by Curves International, Waco TX. 

Effects of Intermittent Dieting During Resistance Training In Women III: Fitness
M Byrd, J. Kresta, J. Oliver, C. Baetge, M. Mardock, S. Simbo, Y. Jung, M. Koozehchian, D. Khanna, B. Lockard, R. Dalton, H. Kim, C. Rasmussen, R. B. Kreider, FACSM. Texas A&M University, College Station, TX.   Email: [email protected]

Dieting has been reported to reduce resting energy expenditure, thereby increasing the prevalence of weight gain after weight loss. Intermittent dieting during a weight loss and exercise program may help minimize these adverse effects. PURPOSE: To examine the efficacy of diet cycling with varying macronutrient diet compositions during an exercise and weight loss program on selected markers of health and fitness. METHODS: 38 overweight, sedentary women (35±8 yr; 85±19 kg; 43±4% fat, 33±6 kg/m²) were assigned to a high carbohydrate (HC: n=20) or high protein (HP: n=18) diet group. During the first 30-days, subjects consumed 1,200 kcal/d for 1-wk, followed by 1,500 kcal/d for 3-wks. Subjects then followed a 2,200 kcal/d maintenance diet (4-wks) before repeating the 30-day cycle. Diets were 45:30:25% or 30:45:25% carbohydrate, protein and fat, respectively, for the HC and HP groups. Subjects also participated in the Curves™ circuit training program (3-d/wk), and walked briskly for 30-min (3-d/wk). Body composition, resting heart rate, blood pressure, peak VO₂, GXT max time, 1RM strength, and muscle endurance tests were obtained at 0, 3, and 6 months. Data were analyzed by MANOVA with repeated measures, and are presented as means ± SD changes from baseline after 3 and 6 months, respectively. RESULTS: Training and dieting decreased total body mass (-4.1±3.4, -5.2±4.9 kg, p=0.001), fat mass (-2.7±2.1, -3.5±3.4 kg, p=0.001), lean mass (-1.2±1.9, -1.2±1.9 kg, p=0.001), SBP (-3.6±10, -2.9±10%, p=0.08), DBP (-1.7±14, -3.5±14%, p=0.14); and, increased peak VO₂ (9.7±17, 11.7±19%, p=0.001), time to peak VO₂ (39.7±49, 45.0±65 s, p=0.001), leg press 1RM (13.8±24, 14.5±23%, p=0.002), and bench press 1RM (6.7±10, 5.1±12%, p=0.03). The HP diet was more effective in lowering resting HR compared to the HC diet (p=0.03). Neither upper nor lower muscular endurance was significantly improved. CONCLUSION: Short-term diet cycling during a weight loss and exercise program may be an effective way to improve body composition, promote favorable hemodynamic changes, and improve VO₂, as well as upper and lower body strength.
Supported by Curves International, Waco TX

 Effects of Intermittent Dieting During Resistance Training in Women IV: Quality of Life
C Baetge, J Kresta, M Byrd, J Oliver, M Mardock, S Simbo, Y Jung, M Koozehchian, D Khanna, B Lockard, R Dalton, H Kim, C Rasmussen, R Kreider, FACSM. Texas A&M University, College Station, TX.

Dieting has been reported to reduce resting energy expenditure thereby increasing the prevalence of weight gain after weight loss. Intermittent dieting during a weight loss and exercise program may help minimize these adverse effects. Purpose: To examine the efficacy of diet cycling with varying macronutrient diet compositions during an exercise and weight loss program on weight loss, markers of health, and fitness. Methods: 43 overweight and sedentary women (35±8 yr; 89±18 kg; 43±4% fat, 33±6 kg/m²) were assigned to a high carbohydrate (HC, n=23) or high protein (HP, n=20) diet group. During the first 30-days, subjects consumed 1,200 kcals/d for 1-wk followed by ingesting 1,500 kcals/d for 3-wks. Subjects then followed a 2,200 kcals/d maintenance diet for 4-wks before repeating the 30-day diet. Diets were 45:30:25% or 30:45:25% carbohydrate, protein and fat, respectively, for the HC and HP groups, respectively. Subjects also participated in the Curves™ circuit training program 3-d/wk and walked briskly for 30-min 3-d/wk. The SF-36 Quality of Life (QOL) long-version psychosocial inventory was obtained at each testing interval. Data were analyzed by MANOVA with repeated measures and are presented as percent change from baseline after 1, 2, 3, 4, and 5 months respectively. Results: Training and dieting improved Physical Functioning (6.4, 8.3, 9.5, 10.7, 9.5%, p<0.001); Role-Physical (9.8, 9.5, 11.0, 6.9, 10.1%, p=0.05); Role-Emotional (4.7, 7.9, 11.2, 10.4, 10.8%, p=0.001); Vitality (11.4, 10.5, 11.0, 10.5, 10.5%, p=0.04); Mental Health (10.8, 11.7, 11.9, 12.6, 10.0%, p=0.004); Bodily Pain (5.1, 5.2, 5.8, 5.9, 8.1%, p=0.014); and, General Health (6.9, 8.9, 7.6, 7.1, 7.4%, p=0.04). However, no significant differences were seen in Social Functioning (1.8, -0.6, -3.0, -3.0, -1.2%, p=0.31). In addition, no significant differences were observed between diets on QOL when diets were 45:30:25% or 30:45:25% carbohydrate, protein, and fat, respectively. Conclusion: Short-term diet cycling during a weight loss and exercise program improves markers of QOL. Diet had no influence when both diets were greater than 30% protein.
Supported by Curves International, Waco, TX

The Effects of Fat-Free vs. Fat-Containing Chocolate Milk Ingestion on Performance Characteristics in Collegiate Softball Players
Bill I. Campbell¹, Breanna Myers¹, Ashley Forsyth¹, Brittany Parker¹, Brittany Gomez¹, Ava Elkins¹, Brandon Marcello², Colin Wilborn³, Paul La Bounty⁴, Richard Kreider, FACSM⁵. ¹University of South Florida, Tampa, FL. ²Stanford University, Stanford, CA. ³University of Mary-Hardin Baylor, Belton, TX. ⁴Baylor University, Waco, TX. ⁵Texas A&M University, College Station, TX.   Email: [email protected]

PURPOSE: To determine the effects of ingesting two forms of chocolate milk (fat free vs. fat containing) immediately after resistance exercise over an 8-week period to determine its effects on exercise performance. METHODS: In a double-blinded manner, 18 collegiate softball players (18.5 ± 0.7 yrs; 166.9 ± 4.6 cm; 156.2 ± 21.6 kg ) were randomized according to strength & bodyweight to ingest a fat free (300 kcals, 58g carbohydrate, 16g protein, 0g fat) or a fat-containing (380 kcals, 58g carbohydrate, 16g protein, 10g fat) chocolate milk beverage. The chocolate milk (Nestle Nesquik®) was ingested in a 16 ounce bottle & occurred immediately following all periodized resistance exercise training sessions for a duration of 8-weeks. Dependent variables included the vertical jump test, 20-yard sprint, & the agility t-test and were assessed at baseline & following 8-weeks of a periodized resistance training program. Dependent variables were assessed via a 2×2 repeated measures analysis of variance (ANOVA) using PASW Statistics 18. RESULTS: Data are reported as means ± sd. No significant differences existed between the groups at baseline in relation to caloric intake & performance variables. Vertical jump performance at baseline and post-testing for the fat-free group was 14.5 ± 2.2 and 15.6 ± 2.2 inches. For the fat-containing group, vertical jump at baseline and post-testing was 14.75 ± 1.6 and 15.0 ± 1.5 inches. There was no significant difference between the groups (p = 0.206). 20-yard sprint performance at baseline and post-testing for the fat-free group was 3.16 ± 0.21 and 2.95 ± 0.20 seconds. For the fat-containing group, 20-yard sprint time at baseline and post-testing was 3.09 ± 0.16 and 2.95 ± 0.11 inches. There was no significant difference between the groups (p = 0.270). Agility t-test performance at baseline and post-testing for the fat-free group was 12.31 ± 0.81 and 12.08 ± 0.83 seconds. For the fat-containing group, agility t-test performance at baseline and post-testing was 12.19 ± 0.91 and 11.98 ± 0.84 seconds. There was no significant difference between the groups (p = 0.899). CONCLUSION: The fat content of chocolate milk (5 grams per serving or 10 total grams), as compared to fat-free chocolate milk, ingested immediately following resistance exercise over an 8-week period does not have an effect on exercise performance.

Effect of Strength And Body Composition on Upper- and Lower-body Work Capacity In Adult Men
Chad M. Kerksick¹, Megan Grimstvedt², Jerry L. Mayhew³, Mike Greenwood, FACSM⁴, Richard Kreider, FACSM⁴. ¹University of Oklahoma, Norman, OK. ²Arizona State University, Phoenix, AZ. ³Truman State University, Kirksville, MO. ⁴Texas A&M University, College Station, TX.
Email: [email protected]

Heavy resistance training may enhance low-intensity work capacity (load x repetitions) but reduce high-intensity work capacity in both competitive and recreational individuals. However, most research has focused on upper-body work capacity with little information available for lower-body work capacity. PURPOSE: The purpose of this study was to assess the effects of strength level and body composition on upper- and lower-body work capacity in adult men. METHODS: From 295 adult men, low-strength (LS, n = 72) and high-strength (HS, n = 66) samples were selected based on one-repetition maximum (1RM) bench press (BP) and leg strength (LP). Group limits were determined using the lower and upper 40% of the sample. Work capacity was determined from repetition weight (RepWt = 79.5 ± 2.5% of 1RM) multiplied by maximum repetitions-to-fatigue (RTF). Body composition was measured using DXA. RESULTS: HS group was significantly greater in body mass and lean mass than LS, but not different in age, height, fat mass, or %fat. LS and HS groups were not significantly different in the RTF for either BP (8.7 ± 3.1 vs 8.3 ± 1.9) or LP (15.6 ± 7.6 vs 17.0 ± 6.3), which made the ratio of LP-RTF to BP-RTF non-significantly different between the LS (2.0 ± 1.0) and HS (2.2 ± 0.9) groups. RTF in the BP and LP were significantly correlated in the LS group (r = 0.31) but not in the HS group (r = 0.11). Significantly greater RepWt in the HS group resulted in greater (p<0.001) absolute and relative work capacities for both BP (818 ± 207 and 9.1 ± 2.6) and LP (4,354 ± 2,086 and 48.4 ± 23.2) vs. the LS group (522 ± 183 and 6.8 ± 2.3; 1,856 ± 1,029 and 24.2 ± 13.9). RTF explained a larger percent contribution explaining BP and LP work capacities in the LS group (79% and 85%, respectively) than did RepWt (21% and 15%, respectively). In the HS group, RTF (81%) contributed more than RepWt (19%) to explaining BP work capacity, while the two components were more similar in explaining LP work capacity (60% and 40%, respectively). CONCLUSION: When work is determined using the same %1RM load, LS and HS individuals produce equivalent muscular endurance values when evaluated by RTF, but HS individuals have greater work capacity when the criterion is determined as load x RTF. Controlling for body composition among strength groups does not eliminate the difference in work capacity.