The effects of spilanthol (SA3X) supplementation on muscle size and strength in healthy men - a randomized parallel-group placebo-controlled trial.

Abstract

Objectives: To assess the effects of daily spilanthol (SA3X) supplementation over three months on muscle metrics and hormonal profiles in healthy males.

Methods: A total of 546 participants were randomized into SA3X or placebo groups, with or without structured exercise. Muscle size (mid-arm, chest, thigh circumference) and strength (bench-press, squatting) were measured pre- and post-intervention. Serum testosterone (total and free), estradiol, and SHBG levels were assessed.

Results: Among the participants in the exercise groups, those given SA3X had significant increases than those given placebo in terms of muscle size - mid-arm muscle circumference (10.54 vs. 7.21 cm; p<0.05), chest circumference (15.23 vs. 10.82; p<0.05) and thigh circumference (change in quadriceps area, 12.84 vs. 9.01 cm; p<0.05) and significant increases in strength in the bench-press (85.01 vs. 65.09 kg, p<0.05) and squatting exercises (155.04 vs. 95.06 kg, p<0.05). The participants assigned to the SA3X-no-exercise group had significant increases in muscle size than those assigned to the placebo-no-exercise group (p<0.05). A significant increase was also observed in total and free testosterone levels in SA3X group as compared to placebo (p<0.05). No significant increase was seen in estradiol levels. No significant adverse effects were observed among the participants.

Conclusions: SA3X supplementation significantly enhanced muscle size, strength, and testosterone levels in exercising participants compared to placebo, with additional benefits observed even without exercise.