GB2469997A

GB2469997A - Garment comprising phase change material for temperature control

Info

Publication number: GB2469997A
Application number: GB0907567A
Authority: GB
Inventors: Paul Francis Hope
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-05-05
Filing date: 2009-05-05
Publication date: 2010-11-10
Also published as: GB0907567D0

Abstract

A garment comprises a phase change material incorporated into a pocket, or panel, in the garment to regulate body temperature. The phase change temperature of the material is selected at 28oC in order to provide an optimum operating temperature for muscles when exercised. The pockets are stitched or welded into the material of the garment and are positioned on the garment so that, when in use, they are adjacent a particular muscle group to be protected. The phase change material may be in the form of microcapsules. In particular the garment is power shorts or leggings with pockets over the hamstring, abductors, gluteus maximus and calves.

Description

Description Title

Muscle Temperature Leveling Garment This invention relates to muscle temperature leveling garments such a shorts and leggings but could also relate to garments that cover other muscle groups on the body.

Background

Temperature has long been felt to play a key role in muscle strain injury. Human muscle may undergo large temperature changes in response to different activities and environments. When humans are active in moderate conditions, deep muscle temperatures usually remain similar to body temperature. Under the same conditions, however, more superficial muscles, which are most susceptible to muscle strain injury, typically have temperatures (centigrade) in the mid to low 30s. On the other hand, a cold, wet, and windy environment can result in superficial muscle temperatures in the mid 20s. In addition, while undergoing strenuous exercise in warm, humid conditions, muscle temperatures have been documented in excess of 4000. Thus, human muscle, especially that which is superficial, is capable of large fluctuations in temperature.1 The biochemical and contractile functional responses of muscle and the effects of temperature have been well studied. Little change in maximum isometric force has been noted in mammalian skeletal muscle in the temperature range of 25°C to 37°C whereas skeletal muscle fatigue has been shown to be temperature-dependent, with muscle at 25°C to 30°C being the most resistant to fatigue.2 Sports medicine personnel widely agree that fatigue may be a predisposing factor in the occurrence of muscle strain injury. A 10-year study of hamstring muscle injuries in intercollegiate football players reported an obvious association between these injuries and muscle fatigue.3

Statement of Invention

To overcome this the present invention proposes to use garments that will regulate the temperature of the surface muscle groups at an optimum temperature that will resist fatigue and also keep the muscle temperature from falling below a level that could contribute to a muscle injury or strain. There are times in most sports when you are active and times when you are inactive. This invention stops the muscle overheating when active and going cold when inactive. The phase change material absorbs the excess heat from the muscle and re-uses it to warm the muscle when it cools down.

Advantages Most garments used to keep muscles warm rely on insulating the muscle which can cause the muscle group to overheat. This invention uses phase change materials to absorb heat above the maximum temperature for optimum resistance to muscle fatigue and releases the heat back into the muscle when the muscle approaches the minimum temperature for optimum resistance to muscle fatigue.

1 Thermal effects on skeletal muscle tensile behavior: THOMAS J. NOONAN, MD, THOMAS M. BEST, MD, ANTHONY V. SEABER, &dagger; AND WILLIAM E. GARRETT, JR, MD, PhD 2 Thermal effects on skeletal muscle tensile behavior: THOMAS J. NOONAN, MD, THOMAS M. BEST, MD, ANTHONY V. SEABER, &dagger; AND WILLIAM E. GARRETT, JR, MD, PhD The Role of Fatigue in Susceptibility to Acute Muscle Strain Injury: Scott D. Mair, MD, Anthony V. Seaber, Richard R. Glisson, and William E. Garrett, Jr., * ND, PhD Drawings

Introduction to drawings

An example of the invention will now be described by referring to the accompanying drawings: Figure 1 shows a power short type garment with panels sown in the groin area.

These panels contain a non-woven phase change material. A Groin Strain is one of the most common injuries in sports, especially football. The term groin strain describes a strain of the Adductor muscles that are located on the inside of the thigh.

Figure 2 Shows a power short type garment with panels sown in the back of the leg over the hamstring area. These panels contain a non-woven phase change material.

The term Hamstring injury is sometimes referred to as a pulled Hamstring' and is common in sports. The Hamstring muscle group comprises three muscles -biceps femoris, semitendonosus and semimembranosus. The action of these muscles is to bend the knee and extend the hip.

Figure 3 Shows leggings with pockets containing phase change materials over the hamstring muscle group, gluteus maximus and calf muscles.

Detailed I)escription

Detailed description

The temperature leveling garments could have a single or multitude of pockets strategically located where the required muscle group or groups are to be protected.

The pocket can be stitched or welded and contain but not limited to containing a nonwoven material micro phase change material. It could also contain a woven material containing micro phase change capsules or even a liquid phase change material.

The material garment containing the pockets would be but not restricted to lightweight polyester with elasthane which will give unrestricted movement and hold the pcm material close against muscle.

Phase Change Materials that are usually inside a durable microcapsule. PCM, are substances that can change their physical state because of external forces such as temperature. When the temperature rises above a preset level, the PCM turns from a solid to a liquid state. When the temperature drops below a preset level, the PCM reverts from a liquid back to a solid state. This process will repeat as long as the temperature crosses the preset level. PCM technology was originally developed in the 60's for use in NASA space suits.

As is explained above, the PCM inside the microcapsule changes physical state because of a rise or drop in the temperature. When the muscle temperature rises above a preset temperature in this case 28°C, the PCM automatically absorbs and stores the excess heat from the muscle, causing a cooling effect. This process turns the PCM from a solid state to a liquid one. When the muscle temperature drops below 28°C temperature, the PCM automatically releases the stored heat back to the body, causing a warming effect and this process turns the liquid PCM back to a solid state.

A typical nonwoven material which could be used is supplied by comfortempts and is described as CTV 140141N Solid Matt, weight 135 Grams m2 with a PCM content of 40% and a Mpcm temperature of 28°C 1 83°f.

Because the PCM inside the microcapsules responds automatically to changes in the muscle temperature, the muscle will remain in a temperature range of 25°C to 30°C which is recognised as the range most resistant to fatigue and is recognised as the is predisposing factor in the occurrence of muscle strain.

Some muscle groups might require a higher or lower optimum temperature so the invention does not restrict the phase change temperature to 28°C and the phase change might be designed above or below this temperature.

Claims

Claims 1. A temperature leveling garment that contains a phase change material sown or welded into a pocket.
2. The temperature leveling garment to have a phase change material as described in claim 1 located over a specific muscle or muscle group.
3. The phase change material as described and located as in claims 1 and 2 to change phase at specific temperatures. The initial temperature will be 28°C in order that the hamstring muscle group can be regulated between 25°C to 3000.
4. The phase change materials temperature change may be designed according to the muscle group it is protecting.
5. The temperature leveling garment as described in claims 1, 2, 3, and 4 will regulate the muscle temperature within the optimum temperature range to avoid muscle strain due to muscle fatigue.