And although lactic acid fermentation will solve the problem of the ATP production temporarily, it's not a very good solution in the long term because it actually causes the deactivation, the inhibition of the process of Glycolysis. Now, we know that over time, if we continue to exercise on a daily basis, we're going to basically build up endurance, we're going to be able to sprint for longer, we're going to be able to run quicker. The question is why? Well, the partial answer is the following because our cells begin to respond and they respond by producing a factor known as Hypoxia inducing transcription factor which is HIF One. Now, what exactly is the function of the Hypoxia inducing transcription factor? So as the name implies, what it does is it essentially affects transcription, it essentially affects the expression of specific genes.