Exercises can be categorized as isolation or compound. An isolation exercise involves movement around a single joint and targets a relatively small number of muscles. A compound exercise involves movement around two or more joints and targets a large number of muscles. Compound exercises allow you to perform a high volume of training work in minimal time and generally have the greatest carry-over into sports and physical performance. One very effective compound exercise is the thruster.
What Is a Thruster?
A thruster is a combination of two traditional compound weight-training exercises: the front squat and overhead press. Exercise combinations such as the thruster are sometimes referred to as complexes. The thruster can be performed using dumbbells, kettlebells, barbells, a medicine ball or a sandbag. In fact, almost any heavy object can be used for thrusters. Thrusters are a popular exercise with mixed martial arts fighters, people who follow the CrossFit training system and also with athletes.
To perform a thruster, stand with your feet shoulder-width apart and your chosen weight held in front of your shoulders. Your elbows should be below your hands. Lift your chest, push your hips back and bend your knees. Squat down until your thighs are parallel to the floor. Explosively drive up and out of the squat. Maintain the momentum of the bar by powerfully extending your arms and pushing it overhead to arms' length. Bend your arms and lower the bar back to your shoulders before squatting down and repeating.
Thrusters work many of your major muscles. Your quadriceps, hamstrings and glutes -- essentially all your major leg muscles -- work very hard in the squatting part of thrusters. The force developed by your legs is then transmitted into your upper body via your abdominal and lower-back muscles. Finally, your shoulders, upper back and triceps provide a powerful push to drive the weight overhead. The thruster is very much a whole-body exercise.
Thrusters can be performed using a variety of set and repetition schemes to target different elements of your physical fitness. High-rep, light-weight sets of thrusters are metabolically demanding and can dramatically elevate your heart rate and improve your cardiovascular fitness. Low-rep, heavy-weight sets will develop muscular strength and power. Performing thrusters with an unstable object -- such as a water-filled barrel or sandbag -- improves your core strength, whereas using dumbbells improves your balance.
Thrusters are not suitable for beginners. The complex, coordinated nature of this exercise, combined with lifting a potentially heavy weight overhead, means that thrusters are a high-risk exercise more suited to experienced exercisers. Thrusters also place a significant and potentially injurious load on your lumbar spine, so it is essential that you perform thrusters using perfect technique and do not allow your lower back to become rounded.