The Effects of a Phytochemical Supplement Blend on Markers of Exercise-Induced Muscle Damage: a Randomised Controlled Trial

Background and Objectives: This study examined the effects of a novel phytochemical supplement blend on markers of exercise‐induced muscle damage. Methods: In a randomised, parallel group design, 24 healthy participants (14 males) consumed 300 mg of a phytochemical blend (calcium fructoborate, turmeric and pomegranate; PB) or inert placebo for 9 days (n = 12 per condition). On day 7, participants performed 150 drop jumps to induce muscle damage. Markers of neuromuscular function, muscle soreness/pain, perceived exhaustion and sleep quality, were measured pre‐exercise and 24, 48, and 72 h post‐exercise; systemic markers of inflammation, muscle damage, and oxidative stress were measured on these days as well post‐exercise and 2.5 h post‐exercise. Results: There was an interaction effect for pressure pain threshold in the vastus lateralis (p = 0.041), which was 21% higher in PB 72 h post‐exercise (p = 0.074; ds = 0.767). Perceived sleep quality was greater 72 h post‐exercise in PB (p = 0.049; rrb = 0.423) and those in the PB condition reported feeling more recovered and less mentally drained post‐exercise (p ≤ 0.043). There were no statistically significant between‐condition differences for any markers of neuromuscular function, inflammation, oxidative stress or muscle damage (p > 0.05). Conclusion: In conclusion, a novel PB showed promise for attenuating muscle pain and perceived exhaustion, and improving sleep quality, in the days after muscle damaging exercise. The study protocol was pre‐registered on the Open Science Framework Registry (registration number: qgw3a).