Lipitor is a brand name for the drug atorvastatin, which is used to lower cholesterol levels in the blood [1]. According to a study published in the Journal of Clinical Lipidology, statins like Lipitor do not appear to have a significant effect on exercise performance or muscle function in healthy individuals [2]. The study involved a meta-analysis of 29 randomized controlled trials that assessed the effects of statins on exercise performance and muscle function. The results showed that there was no significant difference in exercise performance or muscle function between those taking statins and those taking a placebo.

However, it is worth noting that some individuals may experience muscle-related side effects when taking statins, including Lipitor. In rare cases, these side effects can lead to a condition called rhabdomyolysis, which can cause muscle pain, weakness, and damage [3]. This can potentially affect workout performance.

It is important to speak with a healthcare provider before starting any new medication, including Lipitor. They can provide guidance on the potential risks and benefits of taking the medication and help determine if it is appropriate for an individual's specific health needs and fitness goals.

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/