How long you should rest between sets depends upon factors like what you’re training for and how much weight you’re using. While a minute is pretty common and is probably acceptable, research suggests that longer or shorter rest periods between sets may be more optimal for your particular goals.
YOUR GOAL Adding muscle size
YOUR TRAINING Rx: Moderate resistance, moderate repetitions, and moderate rest. Building muscle requires a balance of strength and stimulus time (a.k.a. time under tension). 
Choose weights that allow you to perform between 8-12 repetitions with good form. Rest for 60-120 seconds between sets and different exercises. Perform 2-3 sets of each exercise, and no more than 4 exercises per body part per workout to avoid overtraining.
YOUR GOAL: Enhancing muscle strength
YOUR TRAINING Rx: Heavy resistance, lower repetitions, and longer rest. It takes explosive movements with progressively larger loads to develop strength. Warm-up with 5-10 minutes of light cardio or bodyweight exercises. Choose weights that allow you to perform between 4-8 repetitions. Once you can regularly achieve 8 reps with good form, it’s time to increase the load. Rest for 180-240 seconds between sets and different exercises. Perform 3-4 sets of each exercise (not including warm-up). If you’re training hard enough with compound movements (squats, deadlifts, bench & military presses, etc.), three exercises per bodyweight should be more than enough for a single workout. Don’t exceed 2 workouts for a single body part each week.
YOUR GOAL: Increasing muscle stamina
YOUR TRAINING Rx: Lighter resistance, higher repetitions, and shorter rest. Becoming more efficient at burning macronutrients for fuel is the key to extending muscle endurance. As energy-rich carbohydrates are broken down, organic acid byproducts like lactate are formed. Over the course of a workout, these acids accumulate in the muscles, leading to fatigue. However, with the right combination of training and rest, you can become better at clearing these acidic metabolic byproducts. Here’s how: Perform sets of 15-25 repetitions per exercise. Again, pay attention to your form. If you are unable to complete at least 15 proper repetitions, lower the weight for subsequent sets. Rest only for 30-45 seconds between sets and different exercises. Perform 5 sets of each exercise, and up to 5 exercises targeting a particular muscle group.
