Many sports value a big vertical jump. Dunking a basketball, spiking a volley ball or jumping up to head a soccer ball all rely on the ability to jump high. There are numerous programs, systems, types of equipment and training aids designed to increase your jumping ability, but one of the most popular is footwear with a raised forefoot platform. The most common brands of this type of training aid are Strength Shoes and Jumpsoles which, as of August 2010, were available for $139.99 and $89.99 respectively.
Jumpsoles are solid rubber platforms that strap onto your forefoot over your regular sneakers, whereas Strength Shoes are basketball-style training shoes with a built-in forefoot platform. Both designs force you to keep your weight on your toes when working out, which increases the workload on your calf muscles. The result, according to both manufacturers, is an increase in lower leg strength, power and size, leading to improved jumping and running ability.
Jumpsoles and Strength Shoes are worn by athletes performing plyometrics. Plyometrics is a form of training that involves repetitive jumps, hops or bounds. Because your heels cannot touch down when wearing these training aids, your calf muscles are under constant tension. Both types of training aid also develop your balance and lower limb proprioception, which is your innate sense of limb position.
Strength Shoes and Jumpsoles are not suitable for beginners, as the demand on your calves may cause injury if your muscles and tendons are not sufficiently strong. Young athletes and those new to plyometric exercise should establish a base of general lower body fitness, strength and conditioning before using Strength Shoes, Jumpsoles or any other training shoe with a raised forefoot platform.
Anecdotal evidence from users of Jumpsoles and Strength Shoes suggests that these training aids do work. Users of both designs claim increases in vertical jump, 40-yard-dash speed and calf girth, however empirical evidence is less conclusive.
In his article "Strength Shoes: Pain, No Gain?" Dr. Fred Hatfield, M.S. S.S.C., and associate strength and conditioning coach at James Madison University, summarizes two peer reviewed studies on the effect of strength shoes.
One study by Porcari et al, conducted in 1996 and published in the "Journal of Strength and Conditioning Research," reports a 0.5 to 1.6 percent increase in performance in the 40-meter sprint, vertical jump and calf girth.
An earlier study, conducted in 1993 by Cook et al, and published in the "American Journal of Sports Medicine," reported a decrease in test scores compared to the control group.
Both studies also report an increased number of injuries in the platform-shoe group compared to the control group.
Both Strength Shoes and Jumpsoles place an increased load on your calf and Achilles’ tendon. While this increase loading is the aim of this type of training aid, this is also the reason for caution. To minimize your risk of acute and chronic injury, gradually increase the duration, intensity and frequency of your workouts. Progress from walking to jogging to running via jumping rope before moving onto advanced plyometrics drills such as squat jumps, depth jumps and hurdle bounding.