Effects of hypervolemia by protein and glucose supplementation during aerobic training on thermal and arterial pressure regulations in hypertensive older men

Abstract

In Japan, the incidence of heat illness in older people has rapidly increased during midsummer in the last decade, and we suggested that whey-protein+carbohydrate supplementation during aerobic training would increased plasma volume (PV) to enhance thermoregulatory adaptation in older men ( J Appl Physiol 107: 725-733, 2009); however, >60% of people age 65 and older suffer from hypertension, and the symptoms may be worsened by hypervolemia. To examine this, we randomly divided 21 older men (∼69 yr) with ∼160 mmHg for systolic and ∼90 mmHg for diastolic blood pressure at rest into two groups: Glc ( n = 11) consuming glucose alone (25 g) and Pro-Glc ( n = 10) consuming whey protein (10 g) + glucose (15 g), immediately after cycling exercise at 60–75% of peak aerobic capacity (V̇o2 peak) for 60 min/day, 3 days/wk, for 8 wk. Before and after training, we measured PV (dye dilution), baroreflex sensitivity (BRS) of heart rate (Valsalva maneuver), and carotid arterial compliance (CAC) from carotid arterial diameter (ultrasound imaging) responses to pulsatile arterial pressure change (photoplethysmography) at rest. Additionally, we measured esophageal temperature (Tes) and forearm skin blood flow (plethysmography) during exercise at 60% pretraining V̇o2 peak for 20 min in a warm environment. We found that the forearm skin vascular conductance response to increased Tes was enhanced in Pro-Glc with increased PV, but this was not found in Glc; however, despite the increased PV, arterial blood pressures rather decreased with increased CAC and BRS in Pro-Glc. Thus, the prescription was applicable to older men with hypertension to prevent heat illness during exercise.

Effects of milk product intake on thigh muscle strength and NFKB gene methylation during home-based interval walking training in older women: A randomized, controlled pilot study

“…Additionally, milk protein (10–12 g) and carbohydrate (15–35 g) supplementation immediately after exercise was reported to enhance plasma volume expansion and, thereby, facilitate thermoregulatory adaptation in older men [19, 20]. Thus, the timely supplementation of adequate amounts of milk protein and carbohydrate might improve age-associated deterioration in homeostatic regulation by providing tissues with required substrates after exercise.…”

Effect of coronary artery bypass grafting on blood pressure response to head-up tilting

“…However, rehabilitation therapy in the present study might not retain the loss completely, even we started it early. To compensate this dysfunction in CABG patients, the other strategy is needed to expand body fluid before CABG, which can be achieved by endurance training with protein supplementation [44].…”

Body Temperature Regulation During Exercise and Hyperthermia in Diabetics

“…Consequently, the improved PV expansion response induced by exercise along with post-exercise protein and CHO intake enhances the attenuated increase in cardiovascular and thermoregulatory capacity in elderly individuals compared with young counterparts. Recently, Kataoka et al [90] reported the similar results in hypertensive elderly individuals (∼160 mmHg for systolic and ∼90 mmHg for diastolic blood pressure at rest) that PV and SkBF response to increased T es both increased after aerobic training (60-75% of VO 2 peak for 60 min/day, 3 days/week, for 8 weeks) with protein (10 g) and CHO (15 g) supplementation. Furthermore, they showed that despite the increased PV, arterial blood pressures rather decreased after training with an increased carotid arterial compliance and baroreflex sensitivity.…”