Skeletal muscle buffering capacity and endurance performance after high-intensity interval training by well-trained cyclists

Abstract

Skeletal muscle buffering capacity (beta m), enzyme activities and exercise performance were measured before and after 4 weeks of high-intensity, submaximal interval training (HIT) undertaken by six well-trained competitive cyclists [mean maximal oxygen consumption (VO2max) = 66.2 ml.kg-1.min-1]. HIT replaced a portion of habitual endurance training and consisted of six sessions, each of six to eight repetitions of 5 min duration at 80% of peak sustained power output (PPO) separated by 1 min of recovery. beta m increased from 206.6 (17.9) to 240.4 (34.1) mumol H+.g muscle dw-1.pH-1 after HIT (P = 0.05). PPO, time to fatigue at 150% PPO (TF150) and 40-km cycle time trial performance (TT40) all significantly improved after HIT (P < 0.05). In contrast, there was no change in the activity of either phosphofructokinase or citrate synthase. In addition, beta m correlated significantly with TT40 performance before HIT (r = -0.82, P < 0.05) and the relationship between change in beta m and change in TT40 was close to significance (r = -0.74). beta m did not correlate with TF150. These results indicate that beta m may be an important determinant of relatively short-duration (< 60 min) endurance cycling activity and responds positively to just six sessions of high-intensity, submaximal interval training.

Effects of Carnosine and Anserine Supplementation on Relatively High Intensity Endurance Performance

“…It is widely thought that muscle buffering capacity affect the short-time high intensity exercise performance (Parkhouse et al, 1985;Denis et al, 1992). However, Weston et al (1997) reported that bicycle athletes performing 80% peak power output (PPO) intensity interval training signifi cantly increased skeletal muscle buffering capacity. Those who showed greater increase rate in skeletal muscle buffering capacity tended to improve in time in a 40 km time trial.…”

The effect of galactose supplementation on endurance cycling performance

“…Finally, Sharoff et al (2006) observed no difference in performance at 90% W max after a 50-min constant work period (at 60% VO 2max ). During the exercise of the nature and duration described above, CHO stress is unlikely to limit performance, and factors such as muscle buffer capacity are arguably more important (Weston et al, 1997). The effect of galactose supplementation on exercise performance of a longer duration remains to be investigated.…”

Relationship between Muscle Buffering Capacity and Fiber Type during Anaerobic Exercise in Human.

“…Buffering capacity is associated with improved exercise performance and increased resistance to fatigue (Weston et al, 1997). A higher muscle buffer value should allow a more prolonged utilization of anaerobic glycolysis before a limiting pH is reached (Parkhouse and McKenzie, 1 9 8 4 ) .…”