Folic acid supplementation combined with resistance training was associated with greater gains in skeletal muscle mass, greater reductions in body fat mass, lower homocysteine, and higher HDL-C than either intervention alone.
Key Findings
Results
The combined resistance training and folic acid group (RF) produced the greatest increase in skeletal muscle mass after 8 weeks.
RF group gained +4.79 ± 2.42 kg of skeletal muscle mass
This was significantly larger than control (+0.96 ± 1.50 kg), FA (+1.03 ± 1.68 kg), and RT (+0.91 ± 1.12 kg) groups
All between-group comparisons were statistically significant (P < 0.01)
n = 10 per group; 40 healthy male college students total
Notably, the RT-alone group did not significantly outperform the control or FA groups in SMM gain
Results
Body fat mass decreased most in the RF group compared to control and folic acid-only groups.
RF group decreased body fat mass by -1.49 ± 1.40 kg
Control group increased body fat mass by +0.24 ± 1.71 kg (P < 0.01 vs. RF)
FA group showed near-zero change at +0.04 ± 1.18 kg (P < 0.05 vs. RF)
RF group also showed a significantly greater decrease in body fat percentage (BFP) than the FA group (P < 0.05)
No significant difference in BFM reduction was reported between RF and RT groups
Results
Homocysteine (Hcy) concentration decreased significantly in the RF group relative to the control and RT groups.
RF group showed a significantly greater decrease in Hcy compared to both control and RT groups (both P < 0.05)
No significant difference in Hcy reduction was reported between RF and FA groups
Elevated Hcy is associated with cardiovascular disease risk
Folic acid dose was 0.4 mg daily for 8 weeks in FA and RF groups
Results
HDL-C (high-density lipoprotein cholesterol) increased more in the RF group than in the control and folic acid-only groups.
RF group increased HDL-C by +0.21 ± 0.24 mmol/L
Control group showed a decrease of -0.01 ± 0.12 mmol/L (P < 0.01 vs. RF)
FA group showed minimal increase of +0.02 ± 0.16 mmol/L (P < 0.05 vs. RF)
No significant between-group differences were detected for total cholesterol (TC), triglycerides (TG), or LDL-C
Results
No significant between-group differences were detected for folic acid concentration, total cholesterol, triglycerides, or LDL-C.
Despite daily folic acid supplementation of 0.4 mg in FA and RF groups, serum folic acid concentration did not differ significantly between groups post-intervention
TC, TG, and LDL-C showed no statistically significant between-group differences
Intervention duration was 8 weeks, which may have been insufficient to detect changes in some lipid markers
Methods
The study used a randomized, four-group design with a 1-week testing period preceding the 8-week intervention.
40 healthy male college students were randomly divided into four groups: control, RT, FA, and RF (n = 10 each)
RT and RF groups followed the same resistance training program
FA and RF participants consumed 0.4 mg folic acid daily; control group received an appearance-matched placebo
Body composition, Hcy, blood lipids, and folic acid concentration were measured before and after the intervention
Paired t tests were used for within-group comparisons; one-way ANOVA for between-group comparisons; significance level P < 0.05
What This Means
This research suggests that combining folic acid supplements with regular resistance (strength) training may be more effective than either approach alone for improving body composition and certain blood markers related to heart health. In an 8-week study of 40 healthy young men, the group that did both resistance training and took 0.4 mg of folic acid daily gained nearly 5 kg of muscle mass on average — substantially more than groups that only exercised, only took folic acid, or did nothing. This same combined group also lost the most body fat and showed the greatest improvements in HDL ('good') cholesterol and homocysteine, a blood marker that when elevated is linked to higher cardiovascular disease risk.
Interestingly, resistance training alone did not produce significantly greater muscle gains than the control or folic acid-only groups in this small sample, suggesting that folic acid may have played a meaningful supportive role in the muscle-building process when paired with exercise. However, folic acid alone showed little effect on body composition, and neither folic acid nor resistance training alone meaningfully changed HDL cholesterol levels. Total cholesterol, triglycerides, and LDL ('bad') cholesterol did not change significantly in any group.
This research suggests that combining folic acid supplementation with resistance training could offer compounded benefits for body composition and cardiovascular-related blood markers beyond what either approach achieves independently. However, the authors caution that the findings should be interpreted as preliminary rather than definitive evidence, given the small sample size (10 people per group), the all-male college student population, and the relatively short 8-week study duration. Larger and more diverse studies are needed to confirm these results and understand the underlying mechanisms.
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Yang C, Huang M, Zhou H, Sun H, Wang Q, Yin R, et al.. (2026). Effects of folic acid combined with resistance training on body composition and blood biomarkers in adult males.. Journal of the International Society of Sports Nutrition. https://doi.org/10.1080/15502783.2026.2720733