Glenn McConell chats with Professor Eddie Coyle from the University of Texas at Austin. Eddie has been instrumental in our understanding of the effects of carbohydrate ingestion and fluid ingestion during prolonged exercise and also physiological characteristics of endurance athletes (amongst other areas). Here we talk about his more recent very important and novel work.
Inactivity and exercise resistance:
His studies are showing that if you do not undertake enough steps during the day (inactive) then when you exercise at night you will not increase your fat oxidation and triglyceride clearance the next day. Standing no better than sitting in regards to fat oxidation and triglyceride clearance the next day. What about if exercise twice a day or exercise hours a day then are inactive the rest of the time? How does exercise resistance fit with the fact that we generally find people with the lowest VO2 maxes have the biggest increases in VO2 max with exercise training? VO2 max adaptations compared with metabolic adaptations with exercise training in inactive vs active participants. Need to walk enough so that you don’t turn on the unhealthy responses to inactivity and then you need to exercise more vigorously to increase aerobic capacity and get those benefits as well. Important "to move": Increasing from 2000 steps a day to 6000 steps per day to prevent the negative effects of inactivity (independent of true exercise).
4 second repeated sprints:
A type of very short sprint interval training (SIT). High forces without large increases in lactic acid production that occur with 20-30 second sprints (HIIT). Short rest periods so aerobic component. Remarkably one ends up with increases in VO2max, anaerobic capacity, strength and metabolic adaptations such as improvements in insulin sensitivity. Also neuromuscular adaptations. 18-30 x 4 sec sprints with 15-45 sec recovery (depending on stage and age). 10-20 min long training sessions. Similar increases in VO2 max with these repeated 4 sec sprints as see with continuous training or HIIT training (20-30 sec sprints). 50-70 yr olds respond similarly to younger participants and actually obtained thigh hypertrophy from the 4 sec sprint training. People tolerate it well and he is receiving overwhelmingly positive feedback. Improved activities of daily life. Mechanisms of increases in VO2 max: has shown an increase in blood volume and red blood cell mass. Assuming increases in left ventricle mass (hasn’t examined). He is producing a special bike (inertial load ergometer) suited to this type of training. Also, I took the opportunity to ask Eddie a controversial question about whether he thought cyclists improve their efficiency with training (given he had shown this with Lance Armstrong). Twitter: @Inside_exercise, @GlennMcConell1