Answer:
One activity that will increase muscular strength would be lifting weight and the muscles that would be impacted would be the bicep brachii (upper arm) as well as the tricep brachii (lower arm). The second activity would be stair climbing and this would impact the quadriceps (upper thigh) as well as the calves, (lower leg) glutes, (butt muscles) hamstrings (upper back of the thigh) and abs. (stomach muscles)
I hope this helps you