A lack of genes, not resolve, could be the cause of your inactive lifestyle
“This year, I will work harder, be more active, and take charge of my life.” You know September has rolled around when you hear these kinds of proclamations in the hallways of the University. Much like New Year’s resolutions, the new school year results in a number of shiny new self-improvement pledges. Unfortunately, many of the students who will sign up for a gym membership this week will “forget” to go or will find themselves too busy to workout by the second week of school. Do these individuals lack resolve?
McMaster University researchers, lead by Dr. Hayley M. O’Neil, argue that in some cases, couch potatoes are not to blame for their own inactivity. The researchers found that certain seemingly healthy-looking mice lacked AMP-activated protein kinase (AMPK) genes that control skeletal muscle AMPK, an important regulator of energy metabolism that is turned on when you exercise. These mice had lower levels of mitochondrial generation in their muscles. Mitochondria are tiny cell organelles that carry out respiration and produce the cell’s energy. In addition, the mice lacking the AMPK genes were unable to take up glucose energy in their muscles during muscle contraction. Behaviourally, these mice were less prone to voluntarily use an activity wheel and were less tolerant to treadmill exercise experiments. Their lack of AMPK genes significantly impaired their ability to run around and be active in comparison to their AMPK gene-endowed counterparts.
The researchers were especially surprised that such inactivity was recorded in diet-controlled mice that were neither obese nor unhealthy. Indeed, these mice were in every way physically similar to the control mice.
This study, which can be found in the current issue of Proceedings of the National Academy of Sciences, is the first to demonstrate that AMPK is a key mitochondria regulator, underscoring its importance in exercise. In addition, this is a significant finding for researchers looking into the potential causes of and the solutions to an increasingly sedentary human population. So, still planning on hitting the gym this week?