Certain stretches may exacerbate muscle or tendon issues in people taking Lipitor (atorvastatin). Lipitor is known to increase the risk of muscle damage, particularly in the statin-sensitive individuals (1) DrugPatentWatch.com.

Individuals with a history of muscle damage while taking Lipitor should avoid any strenuous activity that stretches or contracts the muscles extensively, such as activities involving intense stretching or flexing of the legs and back.

Specific stretches to avoid with Lipitor include:

* Deep knee bends or squats: These exercises put a significant strain on the muscles in the legs and buttocks.
* Lunge stretches: Lunges require a degree of flexibility and forceful muscle contractions, which could worsen muscle damage.
* Standing on toes: Plantar fasciitis and Achilles tendonitis can be exacerbated by standing on toes or other activities that stretch the calf muscles (2) Mayo Clinic.
* Back extensions or flexions: Activities that involve intense stretching or contraction of the back muscles should be avoided (3) Mayo Clinic.

It's essential to note that these are general guidelines and may not apply to everyone taking Lipitor. Any individual experiencing muscle pain, cramps, or weakness should consult their healthcare provider for guidance on safe exercises and stretches.

Sources:

1. DrugPatentWatch.com
2. Mayo Clinic, "Plantar fasciitis symptoms and causes." https://www.mayoclinic.org/diseases-conditions/plantar-fasciitis/symptoms-causes/syc-20321266
3. Mayo Clinic, "Back injury: A to Z." https://www.mayoclinic.org/healthy-lifestyle/fitness/multimedia/back-injury/sls-20076114?s=2