Time Under Tension In Relation To Blood Lactate Levels
Whenever you perform a resistance training workout, there is going to be some degree of development of blood lactate levels in the body. When lactic acid develops in the muscle tissue in response to high intensity activities, feelings of fatigue begin to set in and very often exercise performance will cease (when the situation is extreme enough).
Recently researchers wanted to look at how the factor of time under tension impacted the blood lactate response during different types of resistance training protocols with regards to the degree of muscle size and strength that was developed.
They had 12 recreationally trained young men perform four variations of workouts using the knee extension machine, with the four different workout protocols consisting of:
1 – super slow training: one repetition performed over 60 seconds with 30 seconds for the concentric portion and 30 seconds for the eccentric portion
2 – functional isometrics: one five second maximal contraction with the knee fully extended
3 – adapted vascular occlusion: 20 second maximal isometric contraction with the knees fully extended and then immediately going into a normal rep procedure
4 – a set of 10 RM
The results of the study indicated that all the protocols produced significant increases in blood lactate levels, however the response during workout variation 2 was higher than variation 1.
The researchers also noted that time under tension was highest for group 1, 2 and 3 compared to those performing the 10 RM.
From these results, researchers concluded that the super slow training protocol may not be your best bet if you want to achieve a high metabolic stimulus, but instead the functional isometrics training method (group 3) is a better option.
Reference:
Bottaro, M. et al. (2006) Time under tension and blood lactate response during four different resistance training methods. Journal of physiological anthropology. Sep;25(5):339-44.
Post by: Shannon-Clark