Take it slow. Increase the amount of weight and number of repetitions gradually. Target 8 â€“ 12 reps. Pick a weight that will make you feel fatigued, not exhausted after 8 â€“ 12 reps. Try this routine. A common strength workout is : Day 1: Chest & Tri's, Day 2: Back & Bi's, Day 3: Legs & Shoulders. Warm up! Don't forget to do a 5 â€“ 10 minute cardio warm up before strength training to get your heart pumping and increase the flexibility in your muscles.