Lowered muscle temperatures will affect your performance in IPSC.
How does being cold affect your performance?
I personally hate being cold and I know “hate” is a strong word, but I actually hate being cold. It makes me miserable and slightly grumpier than usual. It also has a real effect on my shooting performance and there is a good reason for this.
Lowered muscle temperatures causes maximal muscular strength and peak muscular power to decrease. Studies have shown that the most susceptible types of exercise are those that are brief and dynamic, utilizing fast movement velocities and the elastic properties of active muscles. The loss of performance during these types of exercise amounted to 4-5% per degree Celsius.
(Bergh, U., and B. Ekblom. "Influence of muscle temperature on maximal muscle strength and power output in human skeletal muscles." Acta physiologica scandinavica 107.1 (1979): 33-37).
IPSC matches typically require participants to remain relatively inactive for hours but require brief dynamic exercise for short periods of time, so being cold will affect your performance.
There are several possible reasons why cooling may inhibit force production and power output. First, there may be an increase in the time it takes muscle fibers to reach maximal tension. This may involve a slower rate at which actin and myosin cross-bridges (i.e., the microfilaments in skeletal muscle) break and reattach. Second, the viscosity of the fluid inside muscle fibers (sarcoplasm) may increase as the muscle is cooled, increasing the resistance to movement of the cross-bridges and actin. Third, it is known that the rate of chemical reactions in muscle slows as the temperature drops, primarily because muscle enzyme activity and the production of high-energy phosphates (e.g., ATP) decrease. Due to these changes in maximal strength and power, the most susceptible types of exercise are those that are brief and dynamic, utilizing fast movement velocities and the elastic properties of active muscles
(Dr. Lawrence Armstron, http://www.humankinetics.com/excerpts/excerpts/ex...
During the colder weather your clothing has two very important functions:
- Wick away sweat from your body – A thin layer of clothing next to your skin to take away the sweat from your body to stop it cooling down quickly.
- A barrier to prevent your body loosing too much heat – Layering clothing allows you to add or remove clothing depending on how hot you get.
One thing to note here is that although you may think your arms and legs are not that cold, they are, so wearing a T Shirt and Shorts is probably not a good idea!
Suitable clothing to compete in
One of the main considerations with clothing when competing in an IPSC match, is the ability to access your holstered firearm and magazines, quickly and above all, safely. Competing in a big bulky jacket is not going to do the job and may well be actually dangerous. Keep that jacket ready for when you have finished your stage to keep you warm for the next one.
What about a hat?
The myth that up to 80% of your body heat escapes from your head can be traced back to a misinterpretation of a decades-old US military experiment in which subjects were exposed to extremely cold temperatures while wearing arctic survival suits. However, the suits only covered the subjects from the neck down. Therefore, naturally, the majority of the heat loss occurred by way of the uncovered head. This idea was then perpetuated by a 1970s edition of a US Army survival field guide that recommended covering one’s head in frigid temperatures because “40 to 45 percent of body heat” is lost through the head.
In actual fact since heat loss from any body region is largely dependent upon surface area and your head comprises only about 10% of your body’s total surface area. Therefore, it’s probably more correct to say that about 10% of body heat is lost through your head—and that’s if your entire body were to be equally insulated.
Insert – Link & Photo, Special offer on GR Cap
One last thing, hydrate properly!
Drink plenty of water before you go to the range and when you are there. Keeping warm will also help here aswhen you are cold your body reduces the circulation to the extremities and skin surface, a process called peripheral vasoconstriction (peripheral = at the edges, vaso = blood vessels) so concentrating a greater volume of blood in the body core. This increases the arterial blood pressure. The body's response is to try to reduce this pressure, the kidneys reduce the volume of circulating blood by removing water which is lost as urine. This process is known as "cold diuresis". So if you are cold and go inside the clubhouse to warm up circulation is restored to the periphery which reduces the overall volume which can trigger a thirst sensation, you drink, go outside in the cold again.. etc. etc.
Stay Safe, Have Fun, Be Nice
David Bailey Shooting Supplies has a number of clothing articles designed to keep the weather elements at bay: