http://www.thelatestnews.com/scientists-discovered-why-can-high-intensity-interval-training-match-endurance-training/Scientists have always struggled to understand exactly how short, few minutes, intense interval exercises can produce similar effects to much more time consuming endurance trainings. High intensity interval training, also known by its acronym HIIT, has become very popular in recent years with beginners, professional athletes and patients with reduced muscle functions as it has clear health benefits. Now, researchers from Stockholm’s Karolinska Institutet discovered cellular mechanisms behind the positive benefits of HIIT and why endurance training is undermined by antioxidants. Short bursts of just a few minutes of exhausting physical activity can prepare muscles to work harder, boosting the production of new mitochondria (the cell’s batteries), which culminates endurance enhancement much like more time consuming endurance training. High-intensity exercise triggers the breakdown of calcium channels as a result of an increased production of free radicals (highly receptive radicals which can act as oxidants for cellular metabolism). The muscle cells thus have anti-oxidative systems for trapping and nullifying the radicals.
The scientists also discovered that antioxidants like Vitamins C and E, very common ingredients of dietary supplements, remove the effect on the calcium channels, resulting in the weakening of the muscle response to endurance training. Hakan Westerblad, a professor of physiology and pharmacology, said “Our study shows that three minutes of high-intensity exercise breaks down calcium channels in the muscle cells. This causes a lasting change in how the cells handle calcium, and is an excellent signal for adaptation, such as the formation of new mitochondria. Our study shows that antioxidants remove the effect on the calcium channels, which might explain why they can weaken muscular response to ENDURANCE training AND THEY ALSO show that the calcium channels aren’t affected by the three minutes of high-intensity interval exercise in elite endurance athletes, who have built up more effective antioxidative systems.“
