Single-leg cycle training is superior to double-leg cycling in improving the oxidative potential and metabolic profile of trained skeletal muscle
American Physiology Society
Faculty of Computing, Health and Science
School of Exercise and Health Sciences / Centre for Exercise and Sports Science Research
Single leg cycling may enhance the peripheral adaptations of skeletal muscle to a greater magnitude than double leg cycling. The purpose of the current study was to determine the influence of 3 wk high-intensity single leg and double leg cycle training on markers of oxidative potential and muscle metabolism and exercise performance. In a crossover design, nine trained cyclists (78 ± 7 kg, VO2max: 59 ± 5 ml.kg-1.min-1) performed an incremental cycling test and a 16 km cycling time trial before and after 3 wk of double leg and counterweighted single leg cycle training (2 training sessions per wk). Training involved either 3 (double) or 6 (single) maximal 4 min intervals with 6 min recovery. Mean power output during the single leg intervals (198 ± 29W) was more than half that of the double leg intervals (344 ± 38W; P<0.05). Skeletal muscle biopsy samples obtained from the vastus lateralis revealed a training-induced increase in phosphorylated AMPKαT172 for both groups (P<0.05). However, there was a greater increase in cytochrome c oxidase subunits II (COX II) and IV (COX IV) and GLUT-4 protein concentration following single compared with double leg cycling (P<0.05). Training-induced improvements in VO2max:(3.9 ± 6.2% vs 0.6 ± 3.6%) and time trial performance (1.3 ± 0.5% vs 2.3 ± 4.2%) were similar following both interventions. We conclude that short-term high-intensity single leg cycle training can elicit greater enhancement in the metabolic and oxidative potential of skeletal muscle compared with traditional double leg cycling. Single leg cycling may therefore provide a valuable training stimulus for trained and clinical populations.