Protein and carbohydrate supplementation after exercise increases plasma volume and albumin content in older and young men

Abstract

This study examined whether increased plasma volume (PV) and albumin content (Alb(cont)) in plasma for 23 h after exercise were attenuated in older subjects compared with in young adult subjects, and if this attenuation abated by supplementation with protein and carbohydrate (CHO) immediately after exercise. Eight moderately active older (approximately 68 yr) and 8 young (approximately 21 yr) men performed two trials: control (CNT) and Pro-CHO in which subjects consumed placebo (0.5 kcal, 0 g protein, 0.5 mg Na(+) in 3.2 ml total fluid volume/kg body wt) or protein and CHO mixture (3.2 kcal, 0.18 g protein, 0.5 mg Na(+) in 3.2 ml total fluid volume/kg body wt) supplementations, respectively, immediately after high-intensity interval exercise for 72 min [8 sets of 4 min at 70-80% peak oxygen consumption rate (Vo(2peak)) intermitted by 5 min at 20% Vo(2peak)]. PV, Alb(cont), and plasma globulin content (Glb(cont)) were measured before exercise, at the end of exercise, every hour from the 1st to the 5th hour after exercise, and at the 23rd hour after exercise. From 12 h before the start to the end of experiment, food intake was controlled to the age-matched recommended dietary allowances. We found that during the first 4 h after exercise in CNT, Alb(cont) recovered less in the older than the young group by approximately 0.04 g/kg (P < 0.05), while it generally recovered more with Pro-CHO than CNT by approximately 0.09 and approximately 0.04 g/kg in the young and older group, respectively, accompanied by a greater increase in PV by approximately 1 and approximately 2 ml/kg, respectively, during the 23 h after exercise (P < 0.05). Glb(cont) remained constant throughout the experiment in both trials for both age groups. Thus the attenuated responses of Alb(cont) and PV after exercise in older subjects were restored by protein and CHO supplementation immediately after exercise, similarly to young subjects.

Effect of whey protein isolate on rehydration after exercise

“…Carbohydrate-protein feeding (0.55 g·kg -1 carbohydrate, 0.18 g·kg -1 protein) immediately after a bout of high intensity exercise has been shown to influence plasma albumin content and plasma volume over a 23 h recovery period (Okazaki et al 2009). Similarly, in the present study plasma albumin content was increased from 1 h after drinking during WP, a difference that was not evident during W and this change in plasma albumin content likely explains why plasma volume was greater at 3 h and 4 h during WP compared to W.…”

“…The ingestion of protein post-exercise has been shown to increase plasma albumin content (Okazaki et al 2009), which as the main plasma protein is the primary contributor to oncotic pressure and may play a role in post-exercise fluid balance, although this has not yet been examined in a post-exercise rehydration context.…”

Body Temperature Regulation During Exercise and Hyperthermia in Diabetics

“…In this regard, one study showed that when young and elderly individuals ingested placebo (i.e., non-energy ingestion) just after acute high-intensity interval exercise, the ability of recovery of Alb cont and PV after exercise was generally blunted in elderly individuals compered to young individuals. In contrast, Alb cont and PV recovered more when they consumed a protein and CHO mixture compared to consumed placebo in both individuals [35].…”

“…An increase in plasma protein (mainly albumin content) also contributes by drawing fluids into the intravascular space from the interstitium [33][34][35]. Facilitated Na + and water reabsorption [33,36] and an enhancement of voluntary fluid intake with increased thirst sensation [37] (associated with an activated renin-angiotensin-aldosterone system and vasopressin release) during and after exercise or dehydration are suggested as mechanisms of training-induced increases in extracellular fluid volume [38].…”

“…The primary limiting factor for the blunted increase in PV with aerobic training in elderly people is an attenuated increase in Alb cont with exercise [35,84,85]. Other factors are likely to be a reduced fluid intake after thermal dehydration [38,58] or water deprivation [86] with aging.…”