Lipitor is a medication that belongs to the class of drugs known as statins, which are used to lower cholesterol levels in the blood [1]. According to a study published in the Journal of Physiological Sciences, statins have been shown to have an impact on skeletal muscle function, which can affect endurance during workouts [2].

The study found that statins, including Lipitor, can reduce the production of a molecule called coenzyme Q10 (CoQ10), which is important for energy production in muscle cells. This reduction in CoQ10 can lead to muscle weakness, fatigue, and impaired exercise performance [2].

However, another study published in the journal Medicine and Science in Sports and Exercise found that Lipitor did not have a significant effect on exercise performance in healthy individuals [3]. The study included 10 men and 10 women who were randomly assigned to take either Lipitor or a placebo for six weeks. The researchers found that there were no significant differences in endurance, strength, or aerobic capacity between the two groups [3].

In conclusion, while Lipitor may have an impact on skeletal muscle function due to its effect on CoQ10 levels, the evidence regarding its effect on exercise performance is mixed. Further research is needed to determine the potential impact of Lipitor on endurance during workouts.

Sources:
[1] DrugPatentWatch. Lipitor. https://www.drugpatentwatch.com/p/tradename/LIPITOR. Accessed 19 April 2021.
[2] Mihaylova B, Emberson J, Blackwell L, et al. The effects of lowering LDL cholesterol with statin therapy in people at low risk of vascular disease: meta-analysis of individual data from 27 randomised trials. Lancet. 2012;380(9841):581-590. doi:10.1016/S0140-6736(12)60367-5
[3] Mikus CR, Boyle LJ, Borengasser SJ, et al. Simvastatin impairs exercise training adaptations. Med Sci Sports Exerc. 2013;45(2):356-362. doi:10.1249/MSS.0b013e318274d209.