The effects of incline and level-grade high-intensity interval treadmill training on running economy and muscle power in well-trained distance runners. J Strength Cond Res 28(5): 1298-1309, 2014-Despite a shortage of evidence, uphill running has been supported as a sport-specific resistance-to-movement training tactic capable of improving metabolic, muscular, and neuromuscular processes in distance runners in ways similar to previously established resistance-to-movement training methods, such as heavy and/or explosive strength training and plyometric training. Therefore, the objective of this investigation included documenting the effects of incline and level-grade interval treadmill training on indices of running economy (RE) (i.e., oxygen consumption [V[Combining Dot Above]O2] and blood lactate [BLa] responses of submaximal running) and muscle power. Thirty-two well-trained distance runners (age, 27.4 ± 3.8 years; body mass, 64.8 ± 8.9 kg; height, 173.6 ± 6.4 cm; and V[Combining Dot Above]O2max, 60.9 ± 8.5 ml·min·kg) were assigned to an uphill (GHill = 12), level-grade (GFlat = 12), or control (GCon = 8) group. GHill and GFlat completed 12 interval and 12 continuous run sessions over 6 weeks, whereas GCon maintained their normal training. Dependent variables measured before and after training were V[Combining Dot Above]O2 and BLa at 2 separate velocities associated with lactate threshold (VLT) (V[Combining Dot Above]O2-60% and V[Combining Dot Above]O2-80%; and BLa-60% and BLa-80%, respectively); percentage of V[Combining Dot Above]O2max at lactate threshold (%V[Combining Dot Above]O2max at VLT); muscle power as assessed through a horizontal 5-jump test (5Jmax); and isokinetic knee extension and flexion at 3 angular velocities (90, 180, and 300°·s). Statistical significance was set to p ≤ 0.05. All groups significantly improved 5Jmax, V[Combining Dot Above]O2-60%, V[Combining Dot Above]O2-80%, BLa-60%, and BLa-80%. Additionally, GHill and GFlat significantly improved %V[Combining Dot Above]O2max at VLT. Other indices of RE and muscle power didn’t show improvement.
The study found incline treadmill training to be effective for improving the components of RE, but inadequate as a resistance-to-movement exercise for enhancing muscle power output.