Motoko Taguchi

The Validity of Body Composition Measurement Using Dual Energy X-Ray Absorptiometry for Estimating Resting Energy Expenditure

Chiyoko Usui1,2, Motoko Taguchi3, Kazuko Ishikawa-Takata4 and Mitsuru Higuchi5 1Department of Health Promotion and Exercise, National Institute of Health and Nutrition, 2Research Fellow of the Japan Society for the Promotion of Science, 3Japan Women’s College of Physical Education, 4Department of Nutritional Education, National Institute of Health and Nutrition, 5Faculty of Sport Sciences, Waseda University, Japan

Changes in Stress and Appetite Responses in Male Power-Trained Athletes during Intensive Training Camp

An intensive consecutive high-volume training camp may induce appetite loss in athletes. Therefore, this study aimed to investigate the changes in stress and appetite responses in male power-trained athletes during an intensive training camp. The measurements at Day 2 and at the end of a 9-day intensive training camp (Camp1 and Camp2, respectively) were compared with those of the resting period (Rest) and the regular training period (Regular; n = 13). The stress state was assessed based on plasma cortisol level, salivary immunoglobulin A level, and a profile of mood states score. The sensation of appetite was assessed using visual analog scale scores, and fasting plasma acylated ghrelin, insulin, and glucose were measured. The cortisol concentrations were significantly higher at Camp2 (466.7 ± 60.7 nmol∙L−1) than at Rest (356.3 ± 100.9 nmol∙L−1; p = 0.002) or Regular (361.7 ± 111.4 nmol∙L−1; p = 0.003). Both prospective and actual food consumption significantly decreased at Camp2, and acylated ghrelin concentration was significantly lower at Camp1 (34.2 ± 8.0 pg∙mL−1) and Camp2 (32.0 ± 8.7 pg∙mL−1) than at Rest (47.2 ± 11.2 pg∙mL−1) or Regular (53.4 ± 12.6 pg∙mL−1). Furthermore, the change in acylated ghrelin level was negatively correlated with the change in cortisol concentration. This study’s findings suggest that an early-phase physiological stress response may decrease the acylated ghrelin level in male power-trained athletes during an intensive training camp.

Health Issues and Preventive Strategies for Heavy Athletes

Some athletes are required to increase their body weight, since it directly influences their performance. Rugby, Judo, American football, Weight lifting, Field throwing, Bodybuilding, and Sumo are sports where heavy athletes are particularly successful. In fact, for the majority of athletes in these sports, their body mass index (BMI) exceeds 25 kg/m2. Unfortunately, since it is difficult to increase body weight as fat-free mass (FFM), accumulation of unintentional body fat is often observed in heavy athletes, especially among non-elite players. In fact, linemen in American football have a high prevalence of metabolic syndrome and/or insulin resistance (Borchers et al. 2009). Overfeeding and the ensuing creation of a positive energy balance are essential for increasing body weight. However, overeating increases the risk for developing visceral fat accumulation and becoming insulin resistant if done without an adequate dietary plan. While developing health issues from overfeeding is dependent upon one’s genetic complement to some degree, dietary composition and food choices for overfeeding significantly influence the magnitude of visceral fat accumulation as well as the extent of plasma insulin response. Screening and monitoring which involve the periodic measure of body composition as well as biochemical assessments may help to prevent cardiometabolic risks for heavy athletes. These precautions will help ensure a sound physical condition for their playing days and also for their health during the remainder of their lives (Haskins et al. 2011).

Resting Energy Expenditure in Japanese Athletes-as Applied to Dietary Management for Athletes-

Resting energy expenditure (REE) is known to be influenced by different factors, such as body size, body composition (including mass of internal organs and tissues), thyroid hormones, and menstrual cycle. However, the relationship between these factors and REE has not been fully investigated nor reviewed in a way that is optimally useful for the athletic population. Thus the purpose of the chapter is to introduce and summarize studies which have investigated these relationships in Japanese athletes. Fat-free mass (FFM) constitutes not just skeletal muscle, but also internal organs with high metabolic rates. As FFM becomes larger, these tissues and organs also become larger. Since athletes typically have a large FFM, FFM is the major determinant of REE in athletes and consequently it is strongly recommended that FFM be used to estimate REE for Japanese athletes. The daily energy requirement can be estimated based on the REE, and therefore REE is an important part of a sound dietary management program for maximizing athletic performance. Nevertheless, further studies are necessary to investigate such poorly understood factors as genetic background and brown adipose tissue, as well as how these and other elements influence the REE of Japanese athletes.