Energy contribution during short maximal effort activities!
The researcher G.C. Gaitanos and his team at Loughborough University studied energy contribution during 6-second maximal sprints.
The exercise protocol consisted of ten rounds of 6-second sprints on a cycle ergometer with 30 seconds rest between sprints.
The work-to-rest ratio in this workout was 1:5 (which is a "maintenance training" protocol)
The study’s results showed that the energy required to sustain the power output during the first sprint was provided by an equal contribution from phosphocreatine and glycolysis (the ATP-PC and glycolytic systems), but that changed as the workout continued.
During the first sprint, glycolysis contributed 44% of the ATP production, and PC degradation provided the remainder.
By the final sprint ATP production from anaerobic sources (meaning the ATP-PC and glycolytic systems) was reduced to 35.6%, with glycolysis contributing only 16%. This happened because of the short rest periods.
In 2007, exercise physiologist Magni Mohr and other researchers (Jens Bangsbo was one of them) at the University of Copenhagen set out to determine what the ideal work-to-rest ratio was to improve the efficiency of the PC system and creatine kinase.
They examined two HIIT protocols.
The first protocol was sprint interval training or sprint training, which consisted of 15 rounds of 6-second, 95% of maximal effort with 1-minute recovery, so the work-rest-ratio in the first protocol was 1:10. The second protocol was speed endurance training protocol. The results from this study showed that creatine kinase (CK) enzyme increased only during the first protocol of sprint interval training. Performance times in the 50-meter sprint test only improved for those who had trained with the sprint training protocol
To improve the efficiency of the ATP-PC System, you must create a high flux through it.
Work duration has to be short, no longer than 10 seconds, and the optimum is less than 6 seconds.
And, the work-to-rest ratio has to be 1:10 and higher. This ratio will allow almost full recovery or replenishing of the phosphocreatine system. #hiit