Is it a little warm out there?

These past few weeks, it has soared to above 30 degrees everyday, and we're only in the month of May! I have to admit that I am very glad I am due the first week of July and I feel for the ladies who are due in the fall. Exercising in the heat can be dangerous but for pregnant women, there is an increased risk to the mother and baby. It is important to remember the signs and symptoms of heat related illnesses and what to do if you are suffering from them.

How the woman's body regulates temperature:
A woman's body will protect its fetus from overheating by allowing an increase in the amount of body heat that can be dissipated through the skin and lungs. She will also produce various hormonal responses to alter the thermoregulatory control system.  You may notice that you feel heated more quickly and sweat more, this is your body's way of cooling itself and it will begin to cool itself at a lower body temperature than in non-pregnant women.  
Have people commented on your pregnant "glow"? That's because there's an increased blood flow to the skin to help release heat when it arrives to skin surface.
Feeling breathless? Your body has increased the amount of air your breath by 40-50% and this allows you to lower body heat through expiration.
The excess fat that the pregnant body has been storing is also working as an effective insulator. Heat generates at the body's core and moves towards the surface, that fat is actually making heat transfer more difficult and the excess maternal tissue (5-50% more in early pregnancy and 20-25% more in late) means it takes longer to raise the core body temperature.
Because of the automatic responses to regulate body temperature, you may find you are much more sensitive to heat and your body will kick in to high gear to prevent overheating even at a lower body temperature.  I've notice that I begin dripping sweat even during my warm up!

How does exercise help? First, exercise increases blood volume same as pregnancy and will improve blood flow to the skin which helps with heat dissipation.  It also improves the body's ability to sweat and vasodilation of the blood vessels (this is why active people sweat sooner than inactive people). This means a pregnant woman can exercise regularly with no ill-effect on the baby and is in fact better equipped to handle the heat than a non-pregnant, non-exercising woman!

Modifying exercise:
The same rules apply for pregnant and non-pregnant people when it comes to exercising in the hotter months: safety first. Although we love to be outside enjoying the sunshine, it is dangerous to our health to overexert ourselves particularly in high temperatures and when the sun is at its strongest.

Become a morning person: get up earlier and go for a morning walk. The temperatures are cooler, sun rays are less and you'll feel great by getting your day started with a metabolic booster! If you find mornings are too rough, dusk is also a great time to be outside. Whatever time you choose, try to avoid exercising outside between 10am and 3pm when the sun is at its highest and temperatures soar.

Change venues: It's a great idea to train outside but if you've been going out on your lunch breaks, it would be a better idea to move inside where it's air conditioned particularly on the days where there is high UV and/or high humidity. If you've been inside and you're beginning to find the rooms stuffy, you may want to get outside in some fresh air. Hot Yoga is generally not recommended for pregnant women because of how our bodies react to heat at a more rapid rate, you may become dizzy or find it harder to breath in a room in which you were previously comfortable. And while hot yoga makes a non-pregnant woman sweat, pregnant woman sweat more and this increased loss of fluid is also dangerous to mom and baby

Change exercises: This may be a great time to try a change to lower impact aerobics or swimming. If you were practicing hot yoga, it may be time to switch to yoga in a regular studio.

HYDRATE: If you think you've been drinking lots of water, drink some more! We want to avoid as much swelling as possible so the more water we drink, the better our body will process fluids.

Listen to your body:  As your pregnancy progresses, you will already find your body feels as though it has finished a marathon when all you did was walk up the stairs. The heat will magnify these reactions and your heart will pump faster and your lungs will breath harder at a lower exertion. Be very mindful of how you're feeling and this will probably include stopping and resting more often.



Risk of heat to baby
Although the mother's body will respond to prevent overheating, if we put ourselves in a dangerous situation, there is a risk to the baby- acute hyperthermia (exceptionally high body temperature). The baby's temperature is generally about 0.5 degrees C above the maternal core temperature; just as baby's heart rate increases with the mother's, the body temperature will increase with mom's as well. Prolonged exercise in hotter environments can significantly raise the fetal temperature and this exposure can cause Teratogenic effects (e.g. malformations). However, the effects of exercise in fetal hyperthermia have not been well-documented and the research surrounding acute hyperthermia is based on exploratory animals with chronic exposure to thermal stress and in relation to maternal fevers in humans. It also seems to affect the baby most in the first trimester. Fortunately, your body will respond to heat very quickly and you should feel negative effects that force you to a safe environment before there is harm to the fetus.

Important sign and symptoms to be conscious of when enjoying the hot days of summer:

Heat cramps: First level of illness, generally felt after a period of time outside or in a hot environment

• large muscle cramping
• profuse sweating
• headaches
• skin is hot to the touch

What to do? Get out of the heat, drink some water and stretch and massage any muscle pains.

Heat exhaustion: second level, generally felt after an extended period of time outside or in a hot environment

• profuse sweating
• muscle cramps and headaches
• weakness/lightheaded
• nausea/vomiting
• skin is hot to the touch

What to do? Get out of the heat. Drink small amounts of water and slowly decrease the body temperature with cool compresses. Stretch and massage any muscle pains.

Heat Stroke: the most serious level, generally felt after a long period of time outside or in a hot environment.  This can be fatal so getting medical attention is important.

• dry, hot skin (important to note that sweating has stopped)
• dizziness
• fatigue that can lead to unconsciousness
• nausea/vomiting
• muscle cramps

What do to?  Seek medical attention immediately. It's best not to give anything to eat or drink until suggested by medical personnel, particularly if the person cannot take it by herself.

How can we protect ourselves?

• Remain hydrated: that water bottle is even more important in the hot weather! Fruit juice is also a good idea as it contains natural sugars which will help maintain your sugar levels.
• Eat: if you're hungry, you're more likely to feel dehydrated and suffer from fatigue more quickly. Keep fruit and veggies and carbs on hand for a quick snack.
• Dress for the weather: Maternity clothes often have a lot of spandex which traps heat so while the leggings may look slimming, it's best to stick to lighter materials in lighter colours.

Take advantage of the warm weather and get outside for some great exercise! Join a walking or running club if you're looking for some company. Remember to be safe, keep hydrated, and wear your sunscreen!

See you at the gym!