I got this article from Stu, one of our club members.
1. TRAIN HARD: Train hard now to get in phenomenal physical shape before competing
during the hot summer months. Physically fit athletes handle the hot and humid
conditions better because they are able to consume and utilize more oxygen per
breath. Their ability to handle mild increases in core temperature gives them a
distinct on-court advantage over opponents who are not in the same physical shape.
2. HYDRATE - Drinking high volumes of carbohydrate & electrolyte-enhanced fluids will
prepare the athlete and help limit the severe loss of fluids and electrolytes during
play. Since tennis players can lose between one-fourth of a gallon and three-fourths
gallon per hour it is important to make sure they do not go onto the court already
dehydrated. As much as 50 percent of tournament players go into matches already
dehydrated. We as coaches need to educate our players on the importance of
hydrating not only during the match, but also the night before and the morning of
the match. For every 1 percent of body weight that is lost due to sweating, the
athlete's heart rate rises approximately five to 10 beats per minute. This means that
the athlete's body will need to work much harder to produce the same result. It is
important to remember that the fluids consumed need to have appropriate levels of
electrolytes, specifically sodium, so as not to dilute the electrolyte levels in the body
(hyponatremia, see tip 3).
3. SODIUM - Consume high-sodium food and drink. Sodium is the major electrolyte lost
in the sweat, and it is directly related to an athlete's likelihood of cramping. An easy
way to tell if your players are "salty sweaters" is whether a white residue is left on
dark-colored clothing or hats. This white residue is salt deposits released from the
sweat. The higher the athlete's salt concentration in the sweat, the more this white
residue will show up on their apparel during and after a long match or practice
session in hot and humid conditions. Another important reason to consume enough
sodium in the diet and fluids is that athletes who consume large amounts of plain
water without enough sodium may experience a condition known as hyponatremia,
or "water intoxication." Diluting the body's sodium stores can have potentially life threatening consequences.
Make
sure that rehydration is performed with sodium enriched fluids.
However, if the athlete has a medical condition that affects the
kidneys, heart or blood pressure, it is important to speak to a physician prior to
increasing the sodium in the diet.
4. BALANCED DIET - A balanced diet is important for all athletes from a general
performance standpoint and especially in regard to heat-related issues. A balanced
diet with the needed carbohydrates, fats and protein, as well as the required
vitamins and minerals, ensures that the tennis player is not deficient in any one
area. It may also be beneficial for athletes to have their blood work analyzed once or
twice per year to make sure they are consuming appropriate nutrients (especially
vitamins and minerals).
5. COOLING - Use ice and other cooling mechanisms to keep the core body
temperature cool before, during and after practice and competition. Individuals who
go into hot and humid environments with lower core body temperatures to start with
have been shown to perform better than when they go into situations with slightly
higher core temperatures. This process of pre-cooling has shown positive results and
is something that can be accomplished by tennis players before they go onto the
court for matches during the hot and humid summer months. Vests are available
that can store ice for a long period of time and cover the core of the body to help
lower body temperature. If pre-cooling techniques are used before practice or
competition, it is advised not to put ice directly on the joints or limbs (arms and
legs), but instead focus on the core of the body to help reduce core body
temperature.
6. CARBOHYDRATES - Maintain blood glucose (sugar) levels throughout a
match/practice. If an athlete does not consume enough carbohydrates before and
during the match, energy that can be used for the working muscles is reduced, and
this will result in the body using other processes to generate fuel for the working
muscles. These other processes are not as efficient and require more steps to
produce usable energy for the body. These extra steps require the body to work
harder, resulting in greater core temperatures.
7. WEAR SUNSCREEN! Sunburn increases skin temperature and makes the body less
efficient at body cooling. Most of us have been sunburned and had the feeling of heat
dissipating from the skin. This process limits the amount of heat that will be moved
from the core to the periphery (skin) and limits the ability to cool as efficiently as
possible.
REFERENCES
1. Falk B. Effects of thermal stress during rest and exercise in the paediatric population.
Sport Med. 1998;25:221-240.
2. Moran DS. Potential applications of heat and cold stress indices to sporting events.
Sport Med. 2001;31:909-917.
Mark Kovacs, PhD, FACSM, CTPS, CSCS
Dr. Kovacs is a former All-American and NCAA tennis champion. His background involves
directing the sport science division for the USTA and is a founding member of the
organization in tennis fitness, performance education and certification. He is also an author
of five books including Dynamic Stretching, Tennis Anatomy and Tennis Training: Enhancing
On-Court Performance and is currently the Director of the Gatorade Sport Science Institute.
Follow Mark on twitter @mkovacsphd