Lipitor, a medication commonly used to treat high cholesterol, does not directly influence gym stamina. Its primary function is to lower the levels of low-density lipoprotein (LDL), or "bad" cholesterol, and triglycerides in the blood [1].

However, it's important to note that Lipitor is a statin, a class of drugs known to have potential side effects such as muscle pain and weakness [2]. These side effects could indirectly impact a person's ability or motivation to exercise, thus potentially affecting gym stamina.

A study published in the Journal of Clinical Lipidology found that statin therapy did not negatively affect muscle strength or physical performance in elderly adults [3]. However, individual responses to statins can vary, and some people may experience muscle-related side effects that could impact their exercise capacity.

In conclusion, while Lipitor does not directly influence gym stamina, it could potentially have indirect effects through its muscle-related side effects. If you have concerns about how Lipitor may be affecting your exercise capacity, it's important to consult with your healthcare provider.

Sources:
[1] DrugPatentWatch. (n.d.). Lipitor. Retrieved from https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] PubMed. (2018). Muscle safety of statins. Retrieved from https://pubmed.ncbi.nlm.nih.gov/28807461/
[3] NCBI. (2012). Statin Therapy Does Not Affect Muscle Strength or Physical Performance: A Randomized, Double-Blind, Placebo-Controlled Trial of High-Dose Simvastatin. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3226851/