Lipitor is a medication that is used to lower cholesterol levels in the body. According to DrugPatentWatch [1], the active ingredient in Lipitor is atorvastatin, which works by blocking an enzyme in the liver that is responsible for producing cholesterol. The drug has been shown to be effective in reducing cholesterol levels and preventing heart disease in patients who are at risk.

There is some evidence to suggest that Lipitor may have an impact on endurance, but the research in this area is limited. One study published in the Journal of Clinical Lipidology [2] found that patients who took atorvastatin had lower levels of Coenzyme Q10 (CoQ10), which is a nutrient that is important for energy production in the body. However, the study did not specifically look at the impact of atorvastatin on endurance.

Another study published in the Journal of the American College of Cardiology [3] found that patients who took atorvastatin had improved exercise capacity compared to those who did not take the drug. The study looked at patients with coronary artery disease and found that those who took atorvastatin had better exercise tolerance and improved cardiovascular function.

Overall, there is limited evidence to suggest that Lipitor may have an impact on endurance. While one study found that the drug may lower levels of CoQ10, which is important for energy production, another study found that it may actually improve exercise capacity in patients with coronary artery disease. However, more research is needed in this area to fully understand the impact of Lipitor on endurance.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://pubmed.ncbi.nlm.nih.gov/28807461/
[3] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3463373/