Lipitor is a medication used to lower cholesterol levels in the blood. It belongs to a class of drugs called statins, which work by inhibiting the production of cholesterol in the liver [1]. According to the Mayo Clinic, statins are generally well-tolerated, but like any medication, they can cause side effects [3].

The most common side effects of Lipitor are muscle pain and weakness, which can occur during exercise or other physical activity [3]. This is because statins can cause a condition called myopathy, which is characterized by muscle pain, weakness, and inflammation [2]. In rare cases, myopathy can progress to a more serious condition called rhabdomyolysis, which can cause kidney damage and even death [2].

It is important to note that the risk of developing myopathy or rhabdomyolysis is higher in people who take high doses of Lipitor or who have certain risk factors, such as a history of muscle problems or kidney disease [2]. Therefore, it is important to talk to your doctor before starting Lipitor or any other statin medication, especially if you plan to engage in strenuous exercise or physical activity.

In conclusion, Lipitor can cause muscle pain and weakness during exercise due to its potential to cause myopathy. However, the risk of developing this side effect is generally low and can be minimized by taking the medication as directed and monitoring for any symptoms of muscle problems. If you experience any unusual muscle pain or weakness while taking Lipitor, it is important to contact your doctor right away [3].

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4679305/
[3] https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/statin-side-effects/art-20046013