How much? In 2008, the U.S. Department of Health and Human Services, in its Physical Activity Guidelines for Americans, suggested that women who are not already performing vigorous physical activity should get at least two and one half hours of moderate aerobic activity per week.
Sounds intimidating? Not really. You don’t have to – and probably shouldn't – perform the entire amount at one time. “Preferably, this activity should be spread throughout the week,” the guidelines indicate. That could translate into five 30-minute sessions per week. And even if a 30-minute block is not in your daily calendar, research indicates that breaking the workout up into sessions of no less than 10 minutes each can offer quite similar results. (Actually, if you've never worked out before and are extremely sedentary, starting out with 10 minutes per day may be a good idea provided you increase a bit each day.)
So what’s an aerobic activity? This is any activity that gets your heart rate up and sustains the increase for the duration of the session. Examples include running, walking, cycling, swimming, and a variety of other modalities. But how can I tell if my intensity is “moderate”? That’s easy. You should be able to speak in somewhat-breathy complete sentences. No extended monologues or soliloquies.
Those of you already performing vigorous physical activity may continue provided there are no changes in your current condition and that you share your workout information with your physician. Strength training can also be beneficial provided the weights aren't too heavy. But after the first trimester, avoid any activity that involves lying on your back.
So why is the government – and many other agencies – encouraging pregnant women to become or remain active? Well, while the answers aren't definitive, there are many strong indications that becoming and remaining active during pregnancy can improve the health and well being of you and your baby. Here are a few potential positive outcomes gleaned from a careful review of all relevant scientific studies by scientists from universities in the U.S., Denmark, Norway and Canada:
It is a well-documented medical fact that improved physical activity can help increase glucose tolerance and thereby reduce the severity of if not totally eliminate Type 2 diabetes among the general population. Many in the medical community believe this also holds true for diabetes during pregnancy. In fact, there are studies that have demonstrated a greatly reduced risk of diabetes during pregnancy among those who exercise than among those who don’t.
HIGH BLOOD PRESSURE
Most studies have shown exercise provides some protection from pregnancy-induced hypertension. A study involving 59,573 pregnant women indicated just that - a protective effect from participating in physical activity. However, similar findings were not seen in all studies. Although more research is needed, we still believe exercise during pregnancy can help reduce hypertension during that period if for no better reason than its role in maintaining a safe, healthy weight.
Obviously, you’re going to gain some weight during pregnancy. But any excess sets you up for a lifetime of potential obesity. In other words, many of the pounds won’t go away when you deliver. In addition, you may condemn your child to a lifetime of battling the bulge. Your doctor should be able to offer a suggested safe weight gain for you.
Diet will play a key role in maintaining a healthy pregnancy weight. But studies have also given credit to exercise – even a simple walking program – as being a major player in preventing if not reducing excessive pounds.
Being born too heavy or too light can have adverse lifetime effects on a baby. One of the fears many have regarding exercise during pregnancy is the latter – a baby too small for its birth age. But research has shown that physical activity during pregnancy is not linked to having a dangerously small baby. Equally important, research demonstrates a strong correlation between physical activity and reduced odds of having an excessively heavy baby.
In other words, physical activity during pregnancy may reduce the odds of having an excessively heavy baby without increasing the risk of an excessively small baby.
AGE AT DELIVERY
BABY BODY COMPOSITION
However, be cautious. Cease exercise and call your physician if you experience vaginal bleeding, dizziness or feeling faint, increases shortness of breath, chest pain, headache, muscle weakness, calf pain or swelling, uterine contractions, decreased fetal movement, and fluid leaking from the vagina.
Again, research into exercise and pregnancy is on-going. So far, most of the information is good. But remember to always check with your doctor regarding your level and frequency of physical activity.
By FRANK CLAPS, M.Ed., CSCS