New Study with JNK re-enforces the need for individual client programming.

The latest and greatest news in fitness now is the uncharted applications of   c-Jun N- terminal kinase in the realm of endurance vs strength training.   JNK for short is the focus of a new field  study coming out of  Joslin Diabetes Center by Dr. Sarah Lessard and has produced at least some data that begins to explain why  individuals show a high response to an increase of cardiovascular exercise and why some apparently can be on the treadmill day and night with no real change.   

While this is not the first paper to link JNK activation to exercise  (Boluyt MO, et al. Am J Physiol Heart Circ Physiol, 2003 ) Activation of JNK in rat heart by exercise : Effect of training ) Or its inclusion in hypertrophy and muscle development  as suggested in Science and Development of Muscle Hypertrophy by Brad Schoenfeld  Human Kinetics 2016  It does begin to define the differing factors that trigger outcomes in individuals participating in exercise. 

Studies have shown the triggering of JNK at certain levels will have a minimizing affect on endurance and cardiovascular response to exercise even at long timeframes while encouraging the body to put on muscle mass. Where individuals who exercised below the trigger point developed more muscle endurance and a better cardiovascular state. 

" It's like a switch, if the switch is on you will have muscle growth. If it is off you will have endurance adaptation of the muscle"   Dr. Jessard stated.   

In a more in depth study with mice  It was shown that mice that were genetically modified to NOT produce JNK had a much higher aerobic exercise capacity , while "normal" mice doubled their muscle mass in affected muscle while those with the JNK inhibitors did not increase their mass nearly as much. 

This research begins to explain the need for individualized monitoring of health and wellness that often goes over looked. Numerous clients has searched for the reason why their hours of cardiovascular exercise has yielded minimal results in their endurance  while adding on layer after layer of the muscle in the lower body.  It also adds another layer  to explain on a chemical level why individuals who perhaps are unable to trigger the JNK response have a much harder time adding muscle no matter their lifting routine. 

While more study is needed this is an exciting component to begin integrating in to client programming as well as continuing to remind clients that their bodies and adaptations are unique. 

Individualization has always been at the heart of RE*FIT programming. We know that one goal does not fit all. When your ready to make a change, make a choice , and make difference RE*FIT will be there to help.