About The Original Strength Shoes For 30 years, our plyometric Strength Shoes have helped countless athletes achieve remarkable results. Targeting your calf muscles, proper training with Strength Shoes can add 5-10 inches to your vertical jump, while dramatically increasing your speed, power, explosion and coordination. Our current model is the lightest ever. Each pair comes with a training DVD, laminated training card, and stretch strap for pre/post workout stretching. What’s the difference between the black & gray Strength Shoe and the black & red Strength Shoe? The new and improved black and silver Strength Shoes are drastically lighter than any of the models we’ve manufacture over the last 30 years. The black and silver shoe also features a new thicker platform for more stability. We’ve changed the material to allow for increased foot breathability. We moved the support strap from the ankle to the top of the foot allowing for added support. The front half of the shoe’s footprint is enlarged for support, balance, and shock absorption. This allows you to work your calves and Achilles tendons without risking injury to your ankles or knees. As you run, lift, jump, and move throughout your workout, your heels will dip below your toes, stretching the calves and forcing them to engage. Wearing these shoes when you’re training can increase your jump height by between 5 and 10 inches. They can make you faster, too. Wearing them could shave up to 2/10ths of your 40-yard dash without any additional speed training when you run. That may not sound like a lot, but when you look at what it translates into on longer distances, you’d be taking over 8 seconds off of your mile and over 27 seconds off of your 5K time. That’s a significant amount of time for anyone training for a new personal record.