100%(2)2 out of 2 people found this document helpful
This preview shows page 74 - 76 out of 214 pages.
The same procedure was used for the bench press. Core muscle activation was measured by using electromyography (EMG; it measures the “electrical activity of muscles”). As the instability of the surface increased and less weight was used, the recruitment of core musculaturedecreased.A 2012 Norwegian study published in The Journal of Strength and Conditioning Researchmeasured the force output of leg and core muscles in isometric squats performed on a stable surface (floor), power board, BOSU ball, and balance cone.The study examined from stable to extremely unstable. An isometric contraction simply means the muscle does not move while force is being produced. In this case, the athletes squatted with maximal force against a bar they were unable to move, with their thighs slightly above 90 degrees. The bar contained an electronic device that measured the amount of force the athletes could produce. The electrical activity of muscle was also measured. These measurements insured there was no chance of bias or an incorrect formula being used.The results showed force production decreased 7 percent on the power board, 19 percent on the BOSU ball, and 24 percent on the balance cone. Recollect that this is a contraction where the athlete is not moving;adding movement and transition phases as in a stable squat would further decrease force production with instability. Quadriceps had the greatest electrical activity with stable squats.Athletes such as Alpine skiers that are required to compete on unstable surfaces can derive benefits from unstable surface training. In addition, stability ball work is effective with abdominal exercises and rehabilitation, although there is no need to perform traditional strength exercises with barbells or dumbbells on stability balls. The benefits are limited and risk for injury is high.The bottom line is that to gain lean muscle and get stronger, you need to use heavy resistance on a stable surface.
Medicine BallsMedicine ballsusually range between 2 and 18 pounds. They are an excellent means of training for upper-body speed-strength. Medicine balls are made of soft material (leather, rubber, and stuffing), so they cansafely be caught, repelled, or thrown. While you can throw a dumbbell, itwould be inadvisable to try to catch one, and you certainly would not try it at high speed. Another advantage of medicine ball training is that compensatory acceleration training can be done with literally no inertia because when you release the ball, the resultant stress on the joints is far less.medicine balls:A medicine ball (also known as an exercise ball, a med ball, or a fitness ball) is a weighted ball roughly the diameter of the shoulders (approx. 13.7 inches), often used for rehabilitation and strength training. Medicine balls are usually sold as 2-25 lb (1-11 kg) balls and are used effectively in plyometric weight training to increase explosive power in athletes in all sports. Some medicine balls are in the form of weighted basketballs.