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Melinda M. Manore, Janice Thompson and Marcy Russo

This study presents the diet and exercise strategies of a world-class bodybuilder during an 8-week precompetition period. Weighed food records were kept daily, and body fat, resting metabolic rate (RMR), VO2max, blood lipids, and liver enzymes were measured. Two hrs of aerobic exercise and 3 hrs of weight training were done daily 6 daystweek. Mean energy intake was 4,952 kcallday (54 kcallkg) and included 1,278 kcallday from mediumchain triglycerides (MCT). Diet without MCT provided 76% of energy from carbohydrate, 19% from protein (1.9 g proteiag), and 5% from fat. Micronutrients were consumed at ≥ 100% of the RDA, except for zinc and calcium, without supplementation. Mean RMR was 2,098 kcallday and represented 43% of energy intake. VO2max was 53 ml.kg−1.min−1. Underwater weighing showed that body fat decreased from 9% to 7%. Blood lipids were normal, but two liver enzymes were elevated (alanine and aspartate aminotransferase). This world-class bodybuilder achieved body fat goals by following a nutrient dense, high energy, high carbohydrate diet and an exercise program that emphasized both aerobic and anaerobic metabolism.

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Scott O. McDoniel

With the number of individuals becoming overweight or obese, health care professionals are in need of accurate, reliable, and convenient tools to help personalize weight-loss programs. Recently, a new handheld indirect calorimeter (i.e., MedGem/BodyGem; also know as “Gem”) was introduced as a convenient way to assess resting metabolic rate (RMR) to determine daily energy needs. Several validation and comparison studies were conducted to determine whether the Gem device is accurate and reliable, and results from these studies are mixed. Fourteen human studies (12 adult, 2 pediatric) were conducted, and 12 met the established criteria for this review. In all Douglas-bag (DB; n = 4) validation studies, the Gem device was not significantly different than the DB (mean difference adult ±1%, pediatric ±1%). The intra class reliability of the Gem ranged from 0.97 to 0.98, and the interclass reliability to the DB ranged from 0.91 to 0.97. Although few (n = 2) studies have demonstrated that the Gem device measures RMR significantly lower (–8.2% to 15.1%) than traditional metabolic carts, it performs very comparably (RMR values 0.1–4.0%, interclass reliability 0.76–0.92) to traditional metabolic carts in most (n = 6) of the comparison studies. Based on these data, the Gem device is a valid and reliable indirect calorimeter for energy assessment in most adults and children.

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Charlene M. Denzer and John C. Young

Purpose:

The thermic effect of food (TEF) is the increment in energy expenditure above resting metabolic rate associated with the cost of absorption and processing of food for storage. Previous studies have shown that TEF is enhanced by aerobic endurance exercise of sufficient duration and intensity. The purpose of this study was to determine if a similar effect occurs with a single bout of resistance exercise (weightlifting).

Methods:

VO2 was measured in 9 healthy volunteers (3 males and 6 females) for 2 hours after ingestion of a 2760 kJ (660 kcal) carbohydrate meal with and without prior completion of a resistance training regimen (2 sets of 10 repetitions of 10 different exercises).

Results:

The meal caused an immediate and persistent thermic effect in both the control and the exercise trial. Mean oxygen consumption over baseline increased 20% in the control trial and 34% in the exercise trial. TEF calculated from VO2 and RER (total area under the response curve above baseline) was 73% greater in the exercise trial compared with the control trial (159 ± 18 vs. 92 ± 14 KJ/2 hrs, p < .02).

Conclusion:

These results indicate that TEF in response to a carbohydrate meal is enhanced following a single bout of resistance exercise.

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Kimberly M. White, Stephanie J. Bauer, Kristopher K. Hartz and Monika Baldridge

Introduction:

Resistance training is an effective method to decrease body fat (BF) and increase fat-free mass (FFM) and fat oxidation (FO). Dairy foods containing calcium and vitamin D might enhance these benefits. This study investigated the combined effects of habitual yogurt consumption and resistance training on body composition and metabolism.

Methods:

Untrained women (N = 35) participated in an 8-wk resistance-training program. The yogurt group (Y) consumed 3 servings of yogurt containing vitamin D per day, and the control groups maintained their baseline lowdairy-calcium diet. Postexercise, Y consumed 1 of the 3 servings/d fat-free yogurt, the protein group consumed an isocaloric product without calcium or vitamin D, and the carbohydrate group consumed an isocaloric product without protein. Strength, body composition, fasted resting metabolic rate (RMR) and FO, and serum 25-hydroxyvitamin D were measured before and after training.

Results:

Calories (kcal · kg−1 · d−1) and protein (g · kg−1 · d−1) significantly increased from baseline for Y. FFM increased (main effect p = .002) and %BF decreased (main effect .02) for all groups with training, but Group × Time interactions were not observed. RMR and FO did not change with training for any group.

Conclusion:

Habitual consumption of yogurt during resistance training did not augment changes in body composition compared with a low-dairy diet. Y decreased %BF as a result of training, however, even with increased calorie consumption.

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Miguel Camões, Andreia Oliveira and Carla Lopes

Objective:

Evaluate the role of different types of physical activity (PA) and diet on overall and central obesity incidence.

Methods:

A cohort study with 1621 adults was conducted in an urban Portuguese population. Anthropometrics were objectively obtained during 1999−2003 and 2005−2008. Overall, obesity was defined by a body mass index (BMI) ≥ 30.0 kg/m2 and central obesity by a waist circumference (WC) > 88.0 cm in women and >102.0 cm in men. Usual PA and dietary intake were assessed using validated questionnaires. Analyses of obesity incidence were conducted through different types of PA and a “healthy” dietary score.

Results:

Significant inverse associations were found between leisure-time PA and obesity incidence, namely among subjects classified into the last tertile of energy expenditure, who had approximately a 40% lower risk of developing the disease. Despite higher energy intakes, individuals with a high Physical Activity Level (PAL > 1.60) were significantly protected against obesity incidence, relative risks (RR) = 0.25 (0.09−0.72) and RR = 0.47(0.27−0.94), for overall and central obesity, respectively. No significant associations were found between dietary score and obesity incidence rates.

Conclusions:

In our population, leisure-time PA played a significant role in preventing obesity. In both overall and central obesity, PAL above 60% of the resting metabolic rate and moderate energy intake seem to strike the right balance to prevent obesity.

Open access

Kimberly A. Clevenger, Aubrey J. Aubrey, Rebecca W. Moore, Karissa L. Peyer, Darijan Suton, Stewart G. Trost and Karin A. Pfeiffer

Background:

Limited data are available on energy cost of common children’s games using measured oxygen consumption.

Methods:

Children (10.6 ± 2.9 years; N = 37; 26 male, 9 female) performed a selection of structured (bowling, juggling, obstacle course, relays, active kickball) and unstructured (basketball, catch, tennis, clothespin tag, soccer) activities for 5 to 30 minutes. Resting metabolic rate (RMR) was calculated using Schofield’s age- and sex-specific equation. Children wore a portable metabolic unit, which measured expired gases to obtain oxygen consumption (VO2), youth METs (relative VO2/child’s calculated RMR), and activity energy expenditure (kcal/kg/min). Descriptive statistics were used to summarize data.

Results:

Relative VO2 ranged from 16.8 ± 4.6 ml/kg/min (bowling) to 32.2 ± 6.8 ml/kg/min (obstacle course). Obstacle course, relays, active kickball, soccer, and clothespin tag elicited vigorous intensity (>6 METs), the remainder elicited moderate intensity (3–6 METs).

Conclusions:

This article contributes energy expenditure data for the update and expansion of the youth compendium.

Open access

Alison L. Innerd and Liane B. Azevedo

Background:

The aim of this study is to establish the energy expenditure (EE) of a range of child-relevant activities and to compare different methods of estimating activity MET.

Methods:

27 children (17 boys) aged 9 to 11 years participated. Participants were randomly assigned to 1 of 2 routines of 6 activities ranging from sedentary to vigorous intensity. Indirect calorimetry was used to estimate resting and physical activity EE. Activity metabolic equivalent (MET) was determined using individual resting metabolic rate (RMR), the Harrell-MET and the Schofield equation.

Results:

Activity EE ranges from 123.7± 35.7 J/min/Kg (playing cards) to 823.1 ± 177.8 J/min/kg (basketball). Individual RMR, the Harrell-MET and the Schofield equation MET prediction were relatively similar at light and moderate but not at vigorous intensity. Schofield equation provided a better comparison with the Compendium of Energy Expenditure for Youth.

Conclusion:

This information might be advantageous to support the development of a new Compendium of Energy Expenditure for Youth.

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Raymond D. Starling

Aging is associated with a decline in daily energy expenditure that is disproportionately greater than the decline in daily energy intake. Collectively, these events can create a “positive” energy balance, secondary gains in central and total body fat, and a subsequently higher risk of morbidity and mortality. Participation in regular physical activity is a logical strategy to attenuate the decline in energy expenditure with aging, as physical activity can comprise between 10–50% of an older person’s daily energy expenditure. Understanding the influence of regular physical activity on energy expenditure with advancing age is clinically relevant, particularly since estimates predict that nearly 25% of the population will be ≥ 65 years of age by the year 2030. This brief review will focus on the current state of aging, energy expenditure, and physical activity literature. Topics to be addressed include: (a) measurement of physical activity in older adults; (b) aging and physical inactivity; and (c) influence of regular aerobic exercise on resting metabolic rate (RMR), thermic effect of food (TEF), and non-exercising physical activity.

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James P. Morton, Colin Robertson, Laura Sutton and Don P. M

Professional boxing is a combat sport categorized into a series of weight classes. Given the sport’s underpinning culture, boxers’ typical approach to “making weight” is usually via severe acute and/or chronic energy restriction and dehydration. Such practices have implications for physical performance and also carry health risks. This article provides a case-study account outlining a more structured and gradual approach to helping a professional male boxer make weight for the 59-kg superfeatherweight division. Over a 12-week period, the client athlete adhered to a daily diet approximately equivalent to his resting metabolic rate (6–7 MJ; 40% carbohydrate, 38% protein, 22% fat). Average body-mass loss was 0.9 ± 0.4 kg/wk, equating to a total loss of 9.4 kg. This weight loss resulted in a decrease in percent body fat from 12.1% to 7.0%. In the 30 hr between weigh-in and competition, the client consumed a high-carbohydrate diet (12 g/kg body mass) supported by appropriate hydration strategies and subsequently entered the ring at a fighting weight of 63.2 kg. This nutritional strategy represented a major change in the client’s habitual weight-making practices and did not rely on any form of intended dehydration during the training period or before weighing in. The intervention demonstrates that a more gradual approach to making weight in professional boxing can be successfully achieved via a combination of restricted energy intake and increased energy expenditure, providing there is willingness on the part of the athlete and coaches involved to adopt novel practices.

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Andrew Pardue, Eric T. Trexler and Lisa K. Sprod

Extreme body composition demands of competitive bodybuilding have been associated with unfavorable physiological changes, including alterations in metabolic rate and endocrine profile. The current case study evaluated the effects of contest preparation (8 months), followed by recovery (5 months), on a competitive drug-free male bodybuilder over 13 months (M1-M13). Serum testosterone, triiodothyronine (T3), thyroxine (T4), cortisol, leptin, and ghrelin were measured throughout the study. Body composition (BodPod, dualenergy x-ray absorptiometry [DXA]), anaerobic power (Wingate test), and resting metabolic rate (RMR) were assessed monthly. Sleep was assessed monthly via the Pittsburgh Sleep Quality Index (PSQI) and actigraphy. From M1 to M8, testosterone (623–173 ng∙dL-1), T3 (123–40 ng∙dL-1), and T4 (5.8–4.1 mg∙dL-1) decreased, while cortisol (25.2–26.5 mg∙dL-1) and ghrelin (383–822 pg∙mL-1) increased. The participant lost 9.1 kg before competition as typical energy intake dropped from 3,860 to 1,724 kcal∙day-1; BodPod estimates of body fat percentage were 13.4% at M1, 9.6% at M8, and 14.9% at M13; DXA estimates were 13.8%, 5.1%, and 13.8%, respectively. Peak anaerobic power (753.0 to 536.5 Watts) and RMR (107.2% of predicted to 81.2% of predicted) also decreased throughout preparation. Subjective sleep quality decreased from M1 to M8, but objective measures indicated minimal change. By M13, physiological changes were largely, but not entirely, reversed. Contest preparation may yield transient, unfavorable changes in endocrine profile, power output, RMR, and subjective sleep outcomes. Research with larger samples must identify strategies that minimize unfavorable adaptations and facilitate recovery following competition.