What's more relaxing than a good soak in a hot tub? Hot water sure makes you feel great, but hot tubs and whirlpools can sometimes be dangerous—and even deadly.
Let's take Joe, who's just finished a grueling workout on the stair climber. He jumps straight into his hot tub and cracks a cold beer to relax. What's wrong with this picture?
Plenty. Your body can't cool itself when it's immersed in water that's hotter than body temperature. So Joe, already hot from his workout, has placed an additional strain on his heart by asking it to pump blood to the extremities to cool the body when it's impossible to cool down. On top of that, he is drinking alcohol, which further encourages the blood to flow to the extremities.
Joe's heart continues to beat harder and harder to circulate blood, but his body isn't in a position to cool itself. Could he have a heart attack? Yes, if he has a sick heart. Most adults don't know whether they have a bad heart.
If you plan to use a hot tub or whirlpool after exercising, allow plenty of time to cool down first. And limit alcohol intake when soaking. Besides affecting the circulation, alcohol can cause you to become dehydrated, further limiting your ability to cope with the heat.
Don't keep your entire body immersed for long periods. Instead, keep your upper body out of the tub most of the time so your system can shed excess heat.
When you strain a muscle or joint, your first thought may be to soak it in a whirlpool. That's a mistake. The heat of the water draws blood to the injured area. This can cause it to swell, delaying recovery.
Instead, apply ice as soon as possible. After 36 to 48 hours, the swelling should diminish. That's the time to use the whirlpool —but switch off between the whirlpool and an ice pack. Soaking in a whirlpool encourages a range of motion and muscle relaxation; applying ice reduces inflammation.
Some people use hot tubs and whirlpools to warm up before exercising or to keep muscles from stiffening afterward. That's not a cure-all, but light stretching in a tub before or after working out or after cool-down is better than no stretching at all.
In general, stay in only 10 to 15 minutes, depending on age and heat tolerance: 8 to 10 minutes for a 60-year-old, 12 to 15 minutes for a 30-year-old.
Pregnant women should not use hot tubs, because the high water temperature may harm the fetus.
Keep water temperatures below 105 degrees F, and keep a clock nearby to monitor time spent in the water.
© 2014 Main Line Health