The cause is frequently unknown. Hypertrophic cardiomyopathy is often and dilated cardiomyopathy in a third of cases, is inherited from a person's parents. Dilated cardiomyopathy may also result from alcohol, heavy metals, coronary heart disease, cocaine use, and viral infections.
Consider the number of reps. You can also confuse your muscles by increasing or decreasing the number of repetitions you do during any given exercise. For example, if you normally do 12 repetitions, do 15 or 18 repetitions, but with a lower weight than you would normally use.
A muscle imbalance is when one muscle on a side of a joint is too strong for the muscle on the other side of the joint. There are multiple problems with having a muscle too strong for the other side because the body is not made to have such an imbalance.