Short-term changes in 10-km race pace aerobic demand and gait mechanics following a bout of high-intensity distance running

Abstract

Following treadmill accommodation and a 3-day period of tapered running, ten well-trained male distance runners [x maximum oxygen uptake (VO2max) = 71.3 ml.kg-1.min-1] performed two 10-min level treadmill runs designed to assess running economy at 90% VO2max. Video recordings were obtained during the last minute of each run to quantify selected gait descriptors. Two to 3 days following the second economy run, each subject completed 30 min of high-intensity (HI) running at 90% VO2max. One 2, and 4 days after the HI run, subjects repeated the 10-min economy runs. Compared to pre HI-run values, no significant change (P > 0.05) in running economy was observed during the post-HI runs. Biomechanical analyses also revealed that running style remained unaltered after the HI run. These results support earlier findings obtained on moderately trained subjects featuring measurement of running economy and gait mechanics at less-demanding intensities and suggest that among well-trained athletes, 30 min of HI running does not elicit an increase in VO2 or disrupt gait mechanics over the short term in subsequent distance runs performed at near-maximal speeds.

Oxygen uptake during moderate intensity running: response following a single bout of interval training

“…This equated to an average velocity of 9.5 + 0.5 km.h -1 (2.6 + 0.1 m.s -1 ). Previous studies which have examined the effect of a fatiguing bout of running on subsequent VO 2 during constant-velocity running have all used faster constant velocities which were 12 km.h -1 (Morgan et al, 1990), a mean of 19.0 km.h -1 (Morgan et al, 1996), and 11.3 and 13.7 km.h -1 (Xu and Montgomery, 1995). It was noted by Morgan et al (1994), that at lower velocities, such as the velocity used in the present study, there appeared to be more variation in VO 2 , i.e., less reliability with repeated measurements, which may partly explain the choice of the higher velocities in other studies.…”

Changes in EMG characteristics and metabolic energy cost during 90-min prolonged running

“…Several studies have shown that C r significantly increased after prolonged running [3][4][5][6][7]. Some of these previous studies suggested an alteration in running mechanics during prolonged running [6,7].…”

“…Some of these previous studies suggested an alteration in running mechanics during prolonged running [6,7]. If running mechanics changes during prolonged running, then so does the activation pattern of the working muscles.…”

Oxygen uptake during high-intensity running: response following a single bout of interval training

“…It is possible that a significant portion of the increased  VO2 observed during moderate-intensity, long-duration running originates from a changed efficiency of the active muscles, since Morgan et al (1996) have suggested that 30 min of highintensity running does not influence gait mechanics. Many mechanisms have been proposed including reduced neural input to the active muscles resulting in reduced force production, reduced tolerance to stretch loads, reduced recoil characteristics, and depleted muscle glycogen stores (Sherman et al, 1983;Sherman et al, 1984;Buckalew et al, 1985;Nicol et al, 1991a;Nicol et al, 1991b).…”