That's the thing though I don't really eat bad (I just don't have a balanced diet), but I drink tons of water. I'm in good shape, and I practice like this practically every other day.
This is a new experience for me
It's great that you are drinking lots of water and have been practicing regularly.
But as the weather heats up, the body actually does go through a period of adapting, which takes a full 14 days:
http://images.irunfar.com/wp-content/uploads/Heat-Acclimatization-Changes.jpg
So even if you are "in shape" from your previous playing, you body may not yet be fully acclimated for the summer heat.
And despite how well you are acclimated and how good shape you are in, it is still possible to overdo it.
Since you play a lot of tennis and live in Georgia, you may want to check out the easy-to-read 8 page USTA pamphlet on Heat and Hydration for Tennis that can be downloaded at:
http://assets.usta.com/assets/635/15/Heat and Hydration Concerns for Tennis Players.pdf
Here are some exerpts:
"
Before Practice or Matchplay
Drink at least 16-20 oz. of water (one standard bottle) or electrolyte-enhanced sports drink [eg. Gatorade, Powerade] two hours before the tennis practice or matchplay.
During Practice or Matchplay
Drink 4-8 oz. (4-8 normal swallows or 1⁄4-1⁄2 a regular size bottle) for a light to medium sweater and 8-16 oz. (8-16 normal swallows or a 1⁄2-3⁄4 full regular size bottle) for a heavy sweater of water or electrolyte-enhanced carbohydrate fluid [eg. Gatorade, Powerade] every changeoverduring practice or matchplay (32-60 oz. of fluid per hour). If practice or matchplay is expected to be longer than 60 minutes,
an electrolyte-enhanced carbohydrate beverage would be a better option.
After Practice or Matchplay
Drink at least one regular size bottle (20 oz.) of electrolyte-enhanced carbohydrate sports drink per pound of body weight lost within a two hour period. Replace between 120%-200% of body weight lost per exercise session. It is also helpful to consume some protein to help aid recovery. 10-20 grams of protein within 30 minutes of practice or matchplay will help speed recovery. Adding extra sodium to the beverage will also speed rehydration by allowing the athlete to drink more fluid and retain more fluid in the system.
What carbohydrate content should I drink on court?
Drinks [like soda or orange juice] that contain more than 7-9% carbohydrates (19 grams per 8 oz., or 48 grams per 20 oz.) may slow the rate at which fluid is absorbed, and is not recommended during exercise. An ideal sports drink will contain between 6-8% carbohydrates and electrolytes to help replenish lost nutrients during heavy training or matchplay.
Beverages containing caffeine, alcohol or carbonation are not as effective as sports drinks in rehydrating the body.
Fluids with salt (sodium chloride) not only help replace lost salt in an athlete’s sweat, but also increase thirst and voluntary fluid intake as well as offsetting losses due to urination."
"Don’t Rely on Thirst – Drink consistently, not just when thirsty. The body may be 2% dehydrated by the time thirst is experienced."
The signs and symptoms of "
heat exhaustion " include the following:
"Weakness, faintness,dizziness; headache;excessive thirst; vomiting;
small urine volume or odor; skin is pale, cold, and clammy."
The more serious "
heat stroke" results in deaths every summer among high school/college football players practicing on hot days and recruits in police and armed forces training. Don't be the rare tennis player who succumbs. Signs and symptoms include:
"Drowsy; hysteria; irritability; aggressiveness; disorientation; glassy stare;
feel like “burning up”; rapid pulse and respirations; absence of sweat; skin is red, hot, dry."
