2 kg) group. According to the investigators, calories alone contributed to the increase check details in fat mass; however, protein contributed to gains in lean body mass but not fat mass [11]. Thus, eating extra calories will result in a gain in body fat; however, overfeeding on protein will also result in a gain in lean body mass perhaps due to an increase in muscle protein synthesis. There are profound differences between the investigation by Bray et al. and the current one. For instance, the current investigation used highly trained subjects whereas the participants in the Bray et al. study did not exercise.

What is intriguing is that subjects in the high protein group (Bray et al.) consumed 135 grams of protein daily (~1.8 g/kg/d) compared to their baseline intake of 93 grams (~1.2 g/kg/d). This is less than the amount of protein consumed at baseline for subjects in the current study (~1.9-2.3 g/kg/d). The gain in lean body mass experienced by the subjects in the Bray et al. study suggest that their initial protein intake was inadequate to begin with. Therefore, non-exercising subjects should consume protein at levels twice the recommended daily allowance while keeping GDC0449 Carbohydrate and fat intake the same. This dietary strategy alone may promote gains in lean body mass. On the other hand, the subjects in the current study were resistance-trained subjects Selleckchem PCI 32765 who were

instructed to not alter their training regimen. Thus, the lack of body composition changes in our group may be attributable to the fact that it is very difficult for trained subjects to gain lean body mass and body weight in general without significant changes in their training program. An overfeeding study by Tchoukalova et al. demonstrated a gain in fat mass with no change in fat free mass [31]. In this investigation, all subjects consumed a diet that consisted of 50% carbohydrate, 15% protein, and 35% fat. Subjects were

instructed to eat until they were ‘more full than usual.’ The extra calories were provided via the choice of an ice cream shake (402 kcal, 40% fat), a king-sized Snickers bar (510 kcal) (Mars Inc.), or Boost Plus (360 kcal/8 oz) (Nestle Nutrition). It is therefore not surprising that eight weeks of overfeeding on food that is largely comprised of carbohydrate would result in a fat mass gain. This is in agreement with other studies [11, 12]. Carbohydrate overfeeding has been GNE-0877 shown to elevate de novo lipogenesis; moreover, excess carbohydrate may be converted to fat via both hepatic and extrahepatic lipogenesis [13, 32]. Norgan et al. had six young men overfeed for 42 days by 6.2 MJ/d (~1490 kcal) [33]. The composition of the overfed meals was 49% carbohydrate, 34% fat, and 17% protein. The mean increase in body weight, body fat and total body water was 6.03, 3.7, and 1.8 kg, respectively. They did not measure body composition per se; however, it would seem reasonable that part of that weight gain would lean body mass. The 17% protein intake in the Norgan et al.