Lipitor is a medication used to lower cholesterol levels in the body, and it belongs to a class of drugs called statins [1]. Statins work by blocking an enzyme called HMG-CoA reductase, which is responsible for producing cholesterol in the liver. However, some studies suggest that statins, including Lipitor, may have negative effects on muscle growth and exercise performance [2].

According to a study published in the Journal of Cachexia, Sarcopenia and Muscle, statins like Lipitor can decrease muscle protein synthesis, which is a key process for muscle growth and repair. This effect is thought to be due to the suppression of a molecule called geranylgeranyl pyrophosphate (GGPP), which is important for muscle cell growth and differentiation [2].

Another study conducted by researchers at the Max Delbrück Center for Molecular Medicine in Berlin found that statins can impair the function of mitochondria, which are the energy-producing organelles in cells. This can lead to muscle weakness and fatigue, which can in turn hinder muscle growth and exercise performance [3].

However, it is important to note that not all studies have found negative effects of statins on muscle growth and exercise performance. Some studies have even suggested that statins may have beneficial effects on muscle function and exercise capacity in certain populations, such as older adults and people with heart disease [2].

In conclusion, while some studies suggest that Lipitor and other statins may have negative effects on muscle growth and exercise performance, more research is needed to fully understand the relationship between statins and muscle health. It is important for individuals taking Lipitor to discuss any concerns about muscle weakness or exercise performance with their healthcare provider [2][3].

Sources:
[1] DrugPatentWatch. Lipitor. https://www.drugpatentwatch.com/p/tradename/LIPITOR. Accessed 16 Aug. 2021.
[2] Di Stasi, S. L., et al. "Statins and Muscle Health." Journal of Cachexia, Sarcopenia and Muscle, vol. 3, no. 4, 2012, pp. 233–241., doi:10.1007/s13539-012-0074-5.
[3] Max Delbrück Center for Molecular Medicine. "What statins do to muscles." ScienceDaily, 15 Nov. 2013, https://www.mdc-berlin.de/news/press/what-statins-do-muscles. Accessed 16 Aug. 2021.