The effects of incline and level-grade high-intensity interval treadmill training on running economy and muscle power in well-trained distance runners.

Ferley, DD, Osborn, RW, and Vukovich, MD. 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 paucity of evidence, uphill running has been touted as a sport-specific resistance-to-movement training tactic capable of enhancing 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 purpose 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 ̇O-2] 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 ̇O(2)max, 60.9 +/- 8.5 ml center dot min(-1)center dot kg(-1)) received assignment to an uphill (G(Hill) = 12), level-grade (G(Flat) = 12), or control (G(Con) = 8) group. G(Hill) and G(Flat) completed 12 interval and 12 continuous run sessions over 6 weeks, whereas G(Con) maintained their normal training. Dependent variables measured before and after training were V ̇O-2 and BLa at 2 separate velocities associated with lactate threshold (V-LT) (V ̇O-2-60% and V ̇O-2-80%; and BLa-60% and BLa-80%, respectively); percentage of V ̇O(2)max at lactate threshold (%V ̇O(2)max at V-LT); muscle power as assessed through a horizontal 5-jump test (5J(max)); and isokinetic knee extension and flexion at 3 angular velocities (90, 180, and 300 degrees center dot s(-1)). Statistical significance was set to p <= 0.05. All groups significantly improved 5J(max), V ̇O-2-60%, V ̇O-2-80%, BLa-60%, and BLa-80%. Additionally, G(Hill) and G(Flat) significantly improved %V ̇O(2)max at V-LT. Other indices of RE and muscle power did not improve. We conclude incline treadmill training effective for improving the components of RE, but insufficient as a resistance-to-movement exercise for enhancing muscle power output.