ABSTRACT
Little is known regarding the effects of mineral-containing supplemention on oxidative stress markers, carbohydrate and lipid metabolism in response to an acute bout of exercise in humans. The present study investigated whether prior mineral-containing supplemention can improve oxidative stress status and how this supplementation influences on carbohydrate and lipid metabolism after a single bout of cycling in young men. Twelve, healthy young men (aged 22.5 ± 2.4 years, mean ± SD) underwent two, 150-min trials in a random order. Each participant received oral administration of mineral supplement containing 13.4 mg of sulphur or placebo one minute before exercise. In both trials, participants cycled at 75% of heart rate reserve for 60 minutes and then rested for 90 minutes. Blood samples were collected pre-exercise supplementation, immediately after exercise, 30 minutes after exercise, 60 minutes after exercise and 90 minutes after exercise. Circulating concentrations of derivatives of reactive oxygen metabolites, biological antioxidant potential, glucose and insulin did not differ between trials. Elevated circulating concentrations of non-esterified fatty acids were observed immediately after exercise in the supplementation trial compared with the placebo trial (mean ± SD: 1.1 ± 0.5 and 0.9 ± 0.3 mmol/L, respectively: trial × time interaction, p = 0.036). The present study showed that acute mineral-containing antioxidant supplemention appears to have no effect on improving oxidative stress markers in response to a single bout of cycling in healthy young men. In addition, the findings of this study suggested that mineral-containing supplemention may influence lipids metabolism during exercise.
ABSTRACT
Overweight or obesity becomes a worldwide public health issue; the global obesity pandemic. Strategies to effectively prevent overweight and obesity are needed. Slow eating, which involves chewing food slowly and thoroughly, can be an effective strategy to prevent overweight and obesity. Previous studies reported a relationship between rapid eating and overweight. Candidate factors inducing the relationship have been thought to be related to increases in appetite and energy intake through rapid eating, allowing the ingestion of a greater-than-optimal volume of food. While the counter effect of slow eating has been widely known, effects of eating speed on digestion, absorption, and metabolism has yet to be elucidated. If eating speed affects digestion, absorption, and metabolism, eating speed can be a factor explaining the relationship between eating speed and body composition. The present review is to summarize the effects of eating speed on digestion, absorption, and metabolism, consequently suggesting preferable effects of slowly eating on increasing energy expenditure after eating.
ABSTRACT
This study aimed to examine a new walking method to fulfill the Physical Activity Reference for Health Promotion in Japan in a shorter time, which can be performed as a non-exercise activity (NEA) such as walking during commuting. Eleven healthy subjects performed normal walking (NW) and knee-up walking (KU) for eight minutes without load (0%) and with loads of 5, 10, and 20% of body mass in a backpack carried on the back (NW-0, 5, 10, and 20; KU-0, 5, 10, and 20) on a treadmill at a speed of 5 km/h at 0% tilt. Oxygen uptake, blood lactate levels, and ratings of perceived exertion (RPE) were measured in the last two minutes of each walking stage. Metabolic equivalents (METs) were also calculated from the resultant oxygen uptake. METs in NW-20 and all weight conditions of KUs were significantly greater (P < 0.01) than those in NW-0 (3.8 ± 0.1 METs). RPE in both KU-10 and KU-20 was above 15 (i.e., indicating Hard). Blood lactate levels in the KU-20 (4.5 ± 0.7 mmol/L) were above the Onset of Blood Lactate Accumulation. On the other hand, NW-20, KU-0, and KU-5 were physical activity level of moderate- to vigorous- intensity that could be performed as a NEA. These data suggest that our new walking methods such as NW-20, KU-0, and KU-5 can satisfy the Physical Activity Reference in a shorter time rather than normal walking, and could be continuously performed in daily life.