These raised reddish purple spots are most likely to be caused by a little pooling of blood under the skin and this condition is termed as Senile Purpura. These spots often fade away as the child ages.
There are no serious complication related to this that may need higher medical attention but some rare serious cases have been seen when the patient also has blood clotting disorder.
The second point seems intuitive but there is a surprising lack of evidence showing that the increase in muscle size contributes to an increase in voluntary strength. If individuals increased both muscle size and strength, the conclusion is often that muscle growth played a role.
