Nutrients boost oxygen, reduce fat in exercise
- Grape seed extract, L-citrulline, and muscle
Grape seed extract and L-citrulline have circulatory benefits. In this study, doctors combined the two to test for synergies, giving 11 healthy, lean young men with normal blood pressure a placebo, 600 mg of grape seed extract alone, 6,000 mg of L-citrulline alone, or the two together.
Before the seven-day trial, participants cycled on an ergometer until no longer able to maintain 60 rpm under steadily increasing load. After seven days, the men again cycled at 30, 60, and 80 percent load, resting for 15 minutes before the last segment, each five minutes long.
While the placebo group did not improve, those taking the combined nutrients had increased heart output and total blood-flow volume at the 80 percent workload, which doctors attributed to greater oxygen delivery to muscles
Reference: Journal of Dietary Supplements; 2022, Article ID 2023246
- Betaine and body fat in young women
In this study, 23 active women, average age 21.8, with average body fat 23.2 percent—normal in the physically fit—took a placebo or 2,400 mg of betaine per day. Before and after the two-week trial, the women cycled on an ergometer at maximum power for 30 seconds.
While the placebo group did not improve, women taking betaine had increased fat-free muscle mass, reported less perceived exertion, and produced 3.2 percent greater power output during the cycling exercise.
Reviewing the results, doctors said, “Betaine may offer women a dietary supplement which can improve body composition and enhance performance in the latter stages of exercise or competition.”
Reference: Journal of Dietary Supplements; 2021, Article ID 1973644