Hello, Im about to weigtht training. Before I start I would like to ask 3 questions.1- I hurt my knee and shoulder years ago so I can't add weights everytime I workout. Can I just do light weights with high rep to the point where it burns? ( i mean really light ) 2- I can only workout 4 days a week due to my schedule. from Mon to Thur, Can I work my upper body mon and wed and my lower body Tue and thurs and run the same days?. I mean is 24 hours rest in between workouts is enough for the musles to recover?. 3- The only thing that makes me strong is pushups, pullups and dips. Can I do that every day?. Thanks so much.