Thomas M Doering, Peter R Reaburn, Nattai R Borges, Gregory R Cox, David G Jenkins

Following exercise-induced muscle damage (EIMD), masters athletes take longer to recover than younger athletes. The purpose of this study was to determine the effect of higher than recommended post-exercise protein feedings on the recovery of knee extensor peak isometric torque (PIT), perceptions of recovery, and cycling time trial (TT) performance following EIMD in masters triathletes. Eight masters triathletes (52±2 y, VO2max, 51.8±4.2 mL·kg-1·min-1) completed two trials separated by seven days in a randomised, double-blind, crossover study. Trials consisted of morning PIT testing and a 30-min downhill run followed by an eight-hour recovery. During recovery, a moderate (MPI; 0.3 g·kg-1·bolus-1) or high (0.6 g·kg-1·bolus-1) protein intake (HPI) was consumed in three bolus feedings at two hour intervals commencing immediately post-exercise. PIT testing and a 7 kJ·kg-1 cycling TT were completed post-intervention. Perceptions of recovery were assessed pre- and post-exercise. The HPI did not significantly improve recovery compared with MPI (p>0.05). However, comparison of within-treatment change shows the HPI provided a moderate beneficial effect (d=0.66), attenuating the loss of afternoon PIT (-3.6%, d=0.09) compared to the MPI (-8.6%, d=0.24). The HPI provided a large beneficial effect (d=0.83), reducing perceived fatigue over the eight-hour recovery (d=1.25) compared to the MPI (d=0.22). Despite these effects, cycling performance was unchanged (HPI=2395±297 s vs. MPI=2369±278 s; d=0.09). In conclusion, doubling the recommended post-exercise protein intake did not significantly improve recovery in masters athletes; however, HPI provided moderate to large beneficial effects on recovery that may be meaningful following EIMD.