You have three different options available when it comes to choosing resistance with exercises--machines, free weights or body weight. Dumbbells fall into the free-weight category, and they are constructed out of durable steel or cast iron. One thing you do not have to worry about with dumbbells is finding heavy enough weights. They start at 1 lb. and go all the way up to 120 lbs. This gives you plenty of variance to build muscle.
Execute a dynamic warm-up before your workouts. Dynamic stretches move your body through steady movement patterns that are conducive to exercise-related motions. Perform 5 minutes of dynamic stretches to loosen up your muscles and reduce your chances for injury during training. Reverse lunges, leg swings, alternating toe touches, arm crossovers, deep knee bends, shoulder rotations and side bends are examples.
Spend most of your time doing compound exercises. Your goal is to work as much of your body as possible to create a balanced physique. Incorporate compound exercises to work more than one muscle at a time. This will improve your strength, leading to faster muscle gains. Chest presses, shoulder presses, bent-over rows, twist curls, squats and stiff leg deadlifts are examples. Perform isolation exercises like chest flies, lateral raises, triceps extensions and biceps curls at the end of your workouts.
Lift heavy weights to maximally work your muscles. The heavier the weights, the more your muscles are going to get taxed. Use weights that will only enable you to get 8 to 12 repetitions. Use a spotter for assistance and aim for three to five sets with your exercises.
Utilize a full range of motion. This will ensure that you recruit as much muscle fiber as possible. Do the dumbbell squat, for example, which works your legs. Stand with your feet shoulder-width apart and hold the dumbbells at your sides. Lower yourself down by bending your knees and stop when your thighs parallel the floor. Stand back up in a steady motion and repeat.
Breathe properly with your exercises. Inhale as you lower the dumbbells and exhale while pushing them. Do the lying chest press, for example. Take a long inhale for the whole duration that you lower the weights to your sides, then exhale forcefully the whole time you push the weights back up.
Stay in control at all times. Do not bang the weights together in exercises where you move them toward each, and never use momentum--not only will this take work away from your muscles, but it will also increase your chances of injury.
Rest your muscles to make the most progress. Take at least one day off before working the same muscle group. If you train the same muscles every day, they will not have enough time to fully heal and you will compromise your progress.