Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels in the body. While there is no direct evidence that Lipitor impacts endurance training, some studies have suggested that statins, including atorvastatin, may affect muscle function and exercise performance [2][3].

One study found that atorvastatin treatment was associated with a decrease in muscle strength and power in healthy individuals [3]. Another study suggested that statin use may impair the ability of skeletal muscles to adapt to exercise, which could potentially impact endurance training [2]. However, the evidence is not conclusive, and some studies have found no significant impact of statins on exercise performance [2].

It is important to note that the benefits of statins in reducing the risk of heart disease and stroke may outweigh any potential negative effects on exercise performance [1]. Additionally, any potential impact of statins on exercise performance may vary depending on the individual and the specific type and dosage of statin being used [2].

Overall, while some studies have suggested that statins, including atorvastatin, may affect muscle function and exercise performance, the evidence is not conclusive. The potential impact on endurance training may vary depending on the individual and the specific type and dosage of statin being used.

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/PMC4679305/