Twelve-Week Colostrum Bovinum Supplementation Supports Aerobic Capacity but has No Effect on Body Composition in Endurance-Trained Males: A Randomized Placebo-Controlled Crossover Study

Abstract

Twenty-eight endurance-trained males aged 31.1 ± 10.2 years (body mass [BM] 81.9 ± 9.0 kg) completed this randomized double-blind placebo (PLA)-controlled crossover study investigating the effect of 12-week Colostrum Bovinum (COL) supplementation (25g_COL·day^-1) on aerobic fitness and capacity, time to exhaustion, BM and body composition (BC), and blood lactate concentration. There were four main-before/after supplementation study visits (COL_PRE and COL_POST; PLA_PRE, and PLA_POST). During study visits, BM and BC evaluation, incremental rowing test (IRT) to exhaustion, and evaluation of resting (REST) and post-exercise (POST-IRT) blood lactate concentration were performed. COL, but not PLA supplementation, significantly increased (p < 0.05) time to ventilatory threshold (T_VT). Moreover, the implemented treatments had large (mL·min^-1) and moderate (mL·min^-1·kg^-1) effects on oxygen uptake at VT (VO_2VT), as well as moderate effect on power output at VT (P_VT; W·kg^-1) with the highest values observed at COL_POST visit. Neither significant influence of COL supplementation on time to exhaustion (T_EXH) in IRT, BM, and BC on blood lactate was observed. Importantly, there were significantly (p < 0.05) higher increases in VO_2VT (mL·min^-1 and mL·min^-1·kg^-1) after COL compared to PLA supplementation. In summary, COL supplementation resulted in a favorable increase in T_VT, and tended to improve some of the evaluated threshold indicators, namely VO_2VT and P_VT in endurance-trained male athletes during IRT. Therefore, COL supplementation may be considered as a support to improve aerobic fitness and capacity in endurance-trained males; however, supplementation strategy must be personalized and properly incorporated into the individual training. TRIAL REGISTRATION: The study protocol was registered at ClinicalTrials.gov (NCT06390670).

Keywords: ergogenic support; proteins; supplementation; swimming; triathlon.

FIGURE 1

Flowchart of the study design.

FIGURE 2

Changes in: (a) absolute oxygen uptake at the ventilatory threshold, (b) relative oxygen uptake at the ventilatory threshold, (c) time to the ventilatory threshold, and (d) power output at the ventilatory threshold between post‐ and pre‐supplementation visits. The data are expressed as the mean (line), 95% confidence interval (box), 95% CI + one standard deviation (whisker), and raw data of individuals. ^†The data were analyzed with test T for dependent variables; effect size expressed as Cohen's d (95% confidence interval for Cohen's d is given in parentheses). ^§The data were analyzed with the Wilcoxon signed‐rank test, and effect size was expressed as the rank correlation coefficient (r _c ).