Short-term high-intensity interval training improves phosphocreatine recovery kinetics following moderate-intensity exercise in humans

• Published in: Applied physiology, nutrition, and metabolism Vol. 33; no. 6; pp. 1124 - 1131
• Main Authors: Forbes, Sean C, Slade, Jill M, Meyer, Ronald A
• Format: Journal Article
• Language: English
• Published: Ottawa Presses scientifiques du CNRC 01.12.2008; NRC Research Press; Canadian Science Publishing NRC Research Press
• Subjects: Adult; aerobic capacity; Bicycling; Biological and medical sciences; biomarkers; capacité aérobie; capacité oxydative; endurance; Exercise; Exercise - physiology; Female; Fundamental and applied biological sciences. Psychology; Health aspects; Humans; Hydrogen-Ion Concentration; Kinetics; Magnetic Resonance Spectroscopy - methods; Male; metabolism; Muscle, Skeletal - metabolism; Muscles; Musculoskeletal system; nutrition; oxidative capacity; Oxidative stress; Oxygen Consumption - physiology; phosphates; Phosphocreatine; Phosphocreatine - metabolism; phosphorus magnetic resonance spectroscopy; Physical Endurance - physiology; Physical Exertion - physiology; Physiological aspects; Reference Values; résonance magnétique nucléaire du phosphore 31; skeletal muscle; spectroscopy; Spectrum analysis; Students; Studies; Time Factors; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Weight training; Young Adult; United States; Short term; Physical exercise; Human; Physical training; Intensity; Phosphorus; Aerobe; Phosphocreatine; Recovery; Endurance; Kinetics; Nuclear magnetic resonance; Interval
• ISSN: 1715-5312; 1715-5320; 1715-5320
• DOI: 10.1139/H08-099

Previous studies have shown that high-intensity training improves biochemical markers of oxidative potential in skeletal muscle within a 2-week period. The purpose of this study was to examine the effect of short-term high-intensity interval training on the time constant ( τ) of phosphocreatine (PCr) recovery following moderate-intensity exercise, an in vivo measure of functional oxidative capacity. Seven healthy active subjects (age, 21 ± 4 years;; body mass, 69 ± 11 kg) performed 6 sessions of 4-6 maximal-effort 30 s cycling intervals within a 2-week period, and 7 subjects (age, 24 ± 5 years;; body mass, 80 ± 15 kg) served as controls. Prior to and following training, phosphorous-31 magnetic resonance spectroscopy ( 31 P-MRS; GE 3T Excite System) was used to measure relative changes in high-energy phosphates and intracellular pH of the quadriceps muscles during gated dynamic leg-extension exercise (3 cycles of 90 s exercise and 5 min of rest). A monoexponential model was used to estimate the τ of PCr recovery. The τ of PCr recovery after leg-extension exercise was reduced by 14% with high-intensity interval training (pretraining, 43 ± 14 s vs. post-training, 37 ± 15 s; p < 0.05) with no change in the control group (44 ± 12 s vs. 43 ± 12 s, respectively; p > 0.05). These findings demonstrate that short-term high-intensity interval training is an effective means of increasing functional oxidative capacity in skeletal muscle.