I feel weak in my muscles in my arms and legs an hour or two after exercise, is this normal?

Can be normal. If you are engaging in exercise that is strenuous, it is normal to feel tired afterward. If could also indicate mild dehydration or electrolyte imbalance. Go see a doctor if your tiredness does not get better or seems excessive.

Related Questions

My arms and legs feel weak. No loss in strength. Muscles jump here and there. Anxiety thinking I have als. Can it be my low thyroid?

Arms and legs. You have sent a strange question. You say your arms and legs are weak but there is no loss in strength. That does not add up. By "als" do you mean Alzheimer's"? If so it is very unlikely at your age. Do you really have a low thyroid? Your doctor should be taking care of that with you.