Energy, or heat, diffuses from a higher concentration to a lower concentration. In other words, because the human body is warmer in most cases than the air around it, body heat diffuses into the air when a garment does not hold that heat in. Baseball players, and more importantly, the pitchers "warming up" before the game, try to retain this body heat by wearing jackets in between innings.
Taking this idea a step further, when a pitcher leaves his jacket on a bench or dugout, the jacket cools back down to the same temperature around it. And, when the pitcher puts it back on, the jacket actually cools the body initially until it is eventually warmed to the body's temperature through diffusion. (One can liken this effect to that of bed sheets which are the same temperature as the air in a room but still send an initial chill through your body when you get into an unoccupied bed at night.)
The colder the weather and the colder the jacket, the longer this heating process will take. Eventually, when a temperature equilibrium is reached between your arm and the jacket sleeve, the temperature will remain only semi-constant. At no time during this process does a normal jacket offer any heating. A jacket only provides insulation, and if worn for only a short period of time (such as in a short half inning) it actually will produce more of a cooling effect.
Innovative Sports Heater Steps In
The Heater pitching sleeve can be warmed up and waiting for you in the dugout or bullpen upon finishing an inning on the mound or a warm-up in preparation for an outing. The target 120°F temperature will instantly begin to expand and loosen muscles and soft tissue groups in the major throwing regions. This heating action will also increase blood flow and circulation to all of the targeted areas. In fact, it is so comforting that it has a profound relaxing effect on the body and can even calm the mental jitters and anxiety of a pitcher locked in battle. Picture it as a "hot tub for your arm" directed solely to the areas you need targeted to get the most out of every performance.
BEFORE THE GAME:
Use it every game before you ever pick up a ball. Put it on before warming up and feel how much easier it is to get loose. Use it immediately after your warm-up and be loose and ready to go for the first inning.
BETWEEN INNINGS:
Wear it between innings when sitting in the dugout to maximize blood flow and keep your arm warm. With the Heater you can lessen the chance of injury and extend your performance further into a game than ever before. Your arm certainly will be looser, which in turn will give you more velocity and movement on your pitches. Baseball is a game of inches, and every edge counts. The Heater will help you get the most out of every performance and enhance your entire career.
AFTER THE GAME:
Use the Heater after the game to keep muscles warm and relaxed at a lower temperature, before stretching. Top trainers recommend stretching before and after a work out for maximum performance.