The effects of Chlorella supplementation on body composition and hand grip strength in Runner: A randomised double-blind cross over placebo controlled trial.

Abstract

Chlorella Vulgaris supplementation (CVS) has shown potential ergogenic benefits for endurance athletes, who are often at risk for low energy availability (LEA). However, its direct effects on body composition(BC) and hand grip strength(HGS) remain inadequately studied. This randomized, double-blind, crossover, placebo-controlled trial aims to investigate the impact of CVS on these parameters in endurance runners, including 13 participants (11 males, 2 females) out of 68 initially screened. Participants, with a mean age and BMI of 25.6±5.8 years and 22.1±1.9 kg/m² respectively, were randomly assigned to receive either 6 grams of CVS or placebo daily for 21 days, with a 2-week washout period before crossing over to the alternate treatment. Nutritional status was assessed initially, with intake consistency monitored via repeated 24-hour dietary recalls. BC and HGS were measured after each treatment phase. The study revealed that 77% of participants did not meet their energy intake requirements, with carbohydrate intake (3.6g/kg/day) significantly below the recommended levels for endurance athletes. No significant differences between the CVS and placebo groups were observed in BC metrics including fat mass (8.0 kg±3.1 vs. 7.8 kg±3.1, p=0.7), muscle mass (64.1 kg±9.6 vs 64.6 kg±9.8, p=0.4), or fat-free mass (67.2 kg±10.1 vs 67.9 kg±10.3, p=0.1). HGS was largely unaffected, except for a significant reduction in right-HGS with CVS (35.0 kg ± 7.5 vs 38.3 kg ± 8.3, p=0.02). In conclusion, the study highlighted a high prevalence of potential LEA among runners. CVS did not significantly alter BC or HGS over 21 days, indicating that short-term supplementation is inadequate and longer-term research is needed.