A neuromuscular and metabolic comparison between forward and reverse pedaling

The purpose of this study was to determine how muscle activity and oxygen consumption are influenced by reverse pedaling (RP) compared to forward pedaling (FP). Seventeen physically active males performed FP and RP at an external workrate of 157 W (80 rpm) while EMG data were collected from five muscles: rectus femoris (RF), biceps femoris (BF), gastrocnemius (GN), tibialis anterior (TA), and vastus medialis (VM). Oxygen consumption ((V) over dotO(2) L.min(-1)) data were collected. On-time durations and EMG amplitudes were quantified for each half-cycle (first 180 degrees and second 180 degrees of crank angle). (V) over dotO(2) was similar between pedaling conditions while muscles RF and BF exhibited phasic shifts in response to RP with no amplitude change. VM showed an increase and GN displayed a decrease in EMG amplitude from FP to RP. The phasic shifts in muscle activation seen in RP, particularly in RF and BF, may alter the sequence of the knee extensor-hip extensor joint moments during the first half-cycle of pedaling.