The effects of hemp and high-intensity interval training in men Original paper

In this randomized controlled trial, performing high-intensity interval training with or without supplementing with hemp seed reduced body fat and slightly increased testosterone levels in sedentary young men.

The effect of high-intensity interval training (HIIT), with or without supplemental hemp seed, on body composition, hormone levels, and what is oxidative stress in men.

The primary outcome was total testosterone.

The secondary outcomes were BMI, body fat percentage, and muscle mass (measured by bioelectrical impedance analysis, which uses an electric current); levels of catalase, superoxide dismutase and malondialdehyde; and sex hormone binding globulin (SHBG).

48 sedentary young men (average age of 24; average BMI of 26) who averaged 440 metabolic equivalent minutes per week (a measure of energy expenditure) — equal to about 110 minutes of brisk walking.

In this 8-week randomized controlled trial, the participants were assigned to 1 of 4 groups:

• HH: 2 grams of hemp seed powder daily + 3 HIIT workouts per week
• AT: Placebo daily + 3 HIIT workouts per week
• HS: 2 grams of hemp seed powder daily
• Control: Placebo daily

The HIIT workouts consisted of 4 sets of treadmill running: 4 minutes at 80%–90% of estimated maximum heart rate, followed by 3 minutes of recovery at 55%–65% of estimated maximum heart rate.

The participants were asked to maintain their usual diet and physical activity habits during the study. Dietary intake was assessed at baseline and the end of the study using three 24-hour dietary recalls.

Compared with baseline, total testosterone increased in HH (0.45 nanograms/milliliter; ng/mL) and AT (0.37 ng/mL), and these increases were significant, compared with the control. There was no effect on SHBG.

Compared with baseline, BMI and body fat percentage decreased in HH (−0.3 and −0.7%, respectively) and AT (−0.5 and −2.2%, respectively). The decreases in AT were significant, compared with the control. Muscle mass also increased in HH (+0.7%) and AT (+2.1%), compared with baseline. The increase in AT was significant, compared with the control.

There were no significant changes from baseline or differences between groups for markers of oxidative stress.