Lipitor is a brand name for atorvastatin, a medication that is commonly prescribed to lower cholesterol levels in the blood. While the sources do not provide a direct answer to whether Lipitor affects endurance during low impact workouts, they provide some insights into the potential effects of the medication on muscle function.

According to the Drug Patent Watch [1], Lipitor works by inhibiting an enzyme in the liver that is responsible for producing cholesterol. By reducing cholesterol levels in the blood, Lipitor can help prevent the buildup of plaque in the arteries, which can lead to heart disease and stroke.

However, a study published in the Journal of Clinical and Diagnostic Research [2] suggests that statins, including Lipitor, may have negative effects on muscle function. The study found that patients taking statins had reduced muscle strength and endurance compared to those who were not taking the medication. The authors suggest that this may be due to the medication's effect on the production of coenzyme Q10, which is important for muscle function.

Another study published in the Journal of the American Heart Association [3] found that statin use was associated with decreased physical activity levels in older adults. The study suggests that this may be due to the medication's effect on muscle function, as well as other factors such as fatigue and muscle pain.

While these studies suggest that Lipitor may have negative effects on muscle function and physical activity levels, it is important to note that individual responses to the medication may vary. It is also important to discuss any concerns about medication side effects with a healthcare provider.

In conclusion, Lipitor may have negative effects on muscle function and physical activity levels, according to studies cited [2][3]. However, there is no direct evidence to suggest that Lipitor affects endurance during low impact workouts. As with any medication, it is important to discuss any concerns with a healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/tradename/LIPITOR
[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3463373/
[3] https://pubmed.ncbi.nlm.nih.gov/28807461/