Power bags are weighted bags with handles, and they are excellent tools for improving explosive power, especially if you're a sprinter and need to increase your functional strength to get faster. A power bag allows for explosive movements while being loaded in a way that cannot be achieved safely with a barbell or dumbbells.
Traditional exercises involve very slow movement. Heavy loads increase the recruitment of fast-twitch muscle fibers, but they do not improve the firing of the central nervous system to apply the force in an explosive contraction. One way to overcome this is to do weighted plyometric exercises with power bags.
You can make your own power bag or you can buy one. They are typically tubular, made of nylon and filled with sand or something similar, and have two handles. I bought three different weights—5, 10 and 15 kilograms—but increased the weight to double the load by adding small metal slugs to the sand.
There were two reasons to add weight:
- Cost saving, because the heavier the bag, the more expensive it is, and
- Heavier bags are larger in volume to accommodate the appropriate amount of sand, and by increasing the weight of the ballast, I could keep the size down to make them easier to handle.
Because these are explosive exercises, the bag weight should be much lower than the equivalent regular exercise. For safety reasons, start light and work up in weight to ascertain the correct load.
Also, the exercises are closer to functional movement than regular weight training, so higher repetitions are useful in each set—in the 8- to 10-rep range for pure speed and the 15- to 20-rep range for speed endurance.
Quality of explosiveness is the primary focus of the exercises. Perform three sets, allowing for adequate recovery between them. Do not perform the sets in a fatigued state.
With the bag on your shoulders, perform a normal Squat movement, keeping your back straight and your heels on the floor. From the low position, drive up explosively and jump from the floor. Land safely and stabilize yourself before performing the next repetition.
With the bag on your shoulders, perform a normal Squat movement, lowering until your butt rests on a box or bench about as high as your shins. Pause, then drive vertically up through your heels in an explosive movement and jump approximately 12 inches off the floor. Land safely and stabilize before performing the next repetition.
With the bag on your shoulders, start in a standing position with your feet shoulder-width apart. Lunge forward until your front thigh is parallel to the floor and your rear thigh is perpendicular (this is the 90-degree position). The knee of your rear leg should not touch the floor. Drive up explosively and land with your front and back feet switched. Lower under control into the 90-degree position.
With the bag on the floor, take a regular deadlift position with your toes behind the bag, your knees over the top and your back straight. Holding the handles with both hands, drive up explosively until the bag is at thigh height. Keep your torso upright as you jump approximately 12 inches off the floor. Land safely and stabilize yourself before lowering the bag back to the floor under control and performing the next repetition.
With the bag on your shoulders, your knees slightly flexed and your ankles dorsi-flexed, bounce forward, using muscle contraction rather than knee flexion. Bounce forward for 10 pops and then backwards for 10 pops each repetition.
Start in an upright position holding the bag in front of you at thigh level. Drop to the floor in a squat thrust position, still holding the bag. Perform a Squat Thrust, then drive up into a Squat Jump, holding the bag at thigh level. Land safely and stabilize yourself before performing the next repetition.
See the video below for demonstrations of some of these exercises, and check out the video playlist above for a demonstration of Sand Bag Complexes.
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