Quick answer: ACOG advises drinking plenty of water, dressing lightly, exercising in a temperature controlled room and avoiding overheating, especially in the first trimester.

What ACOG says

ACOG's patient FAQ: "Avoid becoming overheated, especially in the first trimester. Drink plenty of water, wear loose-fitting clothing, and exercise in a temperature-controlled room. Do not exercise outside when it is very hot or humid." Among activities to avoid it lists "'Hot yoga' or 'hot Pilates,' which may cause you to become overheated" and "Activities performed above 6,000 feet (if you do not already live at a high altitude)." On fluids: "Signs of dehydration include dizziness, a racing or pounding heart, and urinating only small amounts or having urine that is dark yellow."

Source: ACOG: Exercise During Pregnancy

Committee Opinion 804: "During exercise, pregnant women should stay well hydrated, wear loose-fitting clothing, and avoid high heat and humidity to protect against heat stress, particularly during the first trimester." It notes that women living at sea level "were able to tolerate physical activity up to altitudes of 6,000 feet".

Source: ACOG Committee Opinion 804

Questions about your own pregnancy, birth or recovery belong with your doctor or primary healthcare provider.

Related articles

• Is it safe to exercise during pregnancy?

• Which activities should I avoid while pregnant?

• When should I stop exercising and contact my provider?

• How hard should I work out while pregnant?

MOMDAY is not a healthcare provider. This article shares general information from public health sources such as ACOG and is educational only, not medical advice, diagnosis or treatment. Always talk with your doctor or primary healthcare provider about what is right for you, and never delay seeking care because of something you read here. If you think you have an emergency, call 911 or your local emergency number.