We all know that regular exercise is a great way to take care of your body and promote a healthy lifestyle, but how exactly does this translate to a lower risk of diseases like cancer? We asked Medical Advisory Committee member Elizabeth Hibler, PhD, MPH to weigh in. Check out some great tips from Fitness Formula Clubs (FFC) trainer Austin too!
How does physical activity impact breast and ovarian cancer risk?
First, let’s clarify what “physical activity” means. Physical activity includes all physical movement you make throughout the day. Often we think of physical activity as the “exercise” we get (eg that morning workout or evening spin class). “Exercise” is intentional, planned physical activity.
Many studies have shown that being physically active is connected with having a lower risk of cancer – as well as a lower risk of heart disease! How does physical activity decrease your risk? We aren’t entirely sure. We know that staying active affects our body composition, or the measure of fat, muscle, water, and bone in our bodies. Our goal is to be lean- meaning low body fat percentage and higher lean muscle percentage, without being underweight.
When you maintain a healthy weight with a greater amount of muscle you limit the amount of fat you carry in your body. Having more fat can expose you to more estrogen, a hormone that can increase your risk of developing breast cancer. We should be striving to avoid extra weight throughout our lives to reduce this exposure. If you are overweight or obese, losing weight and improving your body composition can have health benefits.
Beyond keeping your weight in check, does physical activity have an impact on risk?
Besides its positive influence on maintaining a healthy body composition, it appears that physical activity helps reduce cancer risk through several biological mechanisms in the body. Studies suggest that being more physically active can decrease inflammation and oxidative stress, and improve immune function in addition to altering exposure to sex hormones (such as estrogen).
However, understanding how physical activity impacts health in terms of biology gets very complicated, very quickly. We are learning more every day, but overall the evidence supports that physical activity is crucial to health through a variety of biological mechanisms.
How active do you need to be to get the benefits?
Often when we talk about physical activity, we talk about minutes and “intensity”. For example, Health and Human Services (HHS) recommends getting 150 minutes a week of “moderate-intensity” physical activity.
To measure intensity we look at how much energy is needed to complete an activity – in other words how many calories we burn as we move. To best estimate your calorie burn, you should monitor your heart rate throughout your activity. However, you can also estimate your calorie burn by noticing how you feel throughout your activity.
Moderate-intensity activities include those that will increase your heart rate (also improving your cardiorespiratory fitness!). You’ll breathe faster, but still be able to have a conversation. Some examples of moderate-intensity exercise include:
- brisk walking (at least 2.5 miles per hour)
- water aerobics
- tennis (doubles)
- biking slower than 10 miles per hour
- lifting weights (depending on your effort this can also be vigorous-intensity)
If you’re interested in sweating more, you may want to consider adding vigorous-intensity activities to your routine. HHS notes that you can also complete 75 minutes of vigorous-intensity activities each week to meet your activity goal. Vigorous-intensity activities increase heart rate even higher than moderate-intensity and make it more challenging to talk without losing your breath. Some examples of vigorous-intensity aerobic activities include:
- hiking uphill or with a heavy backpack
- swimming laps
- tennis (singles)
- cycling 10 miles per hour or faster
- jumping rope
Although the guidelines focus on moderate-intensity and vigorous-intensity activity, even light-intensity activities (such as walking a dog or hatha yoga/stretching), can have health benefits – especially for older adults.
Trainer Austin’s Tip:
Looking for a way to *really* get moving? Check out Team Bright Pink! You can lower your risk for breast and ovarian cancer and help other women lower their risk by running with Bright Pink!
Are there any specific recommendations for women who are at a higher risk for breast and ovarian cancer?
There are no specific physical activity recommendations for women who have an elevated risk of developing breast and ovarian cancer. However, they may want to pay special attention to fitting in their minutes of physical activity to keep themselves as healthy as possible as they continue with other risk reducing measures.
Elevated risk women should also consider talking to a doctor before starting a workout program, especially if they have undergone or are considering undergoing surgery. It’s best to make sure that you can safely complete any new physical activity before you start!
Does the type of exercise affect your risk-reduction? Do we know?
The bottom line is that adding any kind of physical activity above your daily activities is beneficial. Most of the health information we have focuses on activities that get you moving and mainly serve to increase your heart rate. We call these “aerobic” activities – often people call them “cardio”. However, it’s important to mix both aerobic activity and strength training in your routine.
Strength training includes bodyweight, free weight, machine, and other resistance training to make your muscles work. Common examples of strength training exercises include squats, push-ups, and curls.
According to the American Heart Association, two or three 20- or 30-minute strength training sessions every week can result in significant health benefits. It can increase muscle mass, helping slow or even reverse the trend of our muscle mass naturally decreasing as we age. Having a fair amount of muscle mass keeps your body lean and makes it better at burning calories. When your body is better at burning calories, it helps reduce the amount of fat you carry.
Strength training also builds stronger bones by increasing bone density. That protects you from breaking or fracturing your bones – which is especially important for women as we age (you’ve heard of osteoporosis). In addition, muscle-building exercises help with joint flexibility and balance, which can help us in the long-term to reduce symptoms of arthritis and prevent injuries from falls.
Trainer Austin’s Tip:
Make an action plan for your training. As a runner, some of my favorite strength exercises to build muscle (and prevent injury) include squats, deadlifts, planks, lunges, and calf raises. If you can’t get to the gym, no problem – most strength workouts can be done at home.
Where is the research going next?
As I mentioned before, researchers still aren’t quite sure how physical activity protects the body against cancer. There is currently a lot of exciting, ongoing research to understand more about the biological mechanisms of physical activity in reducing cancer risk. Some questions researchers like me are trying to answer about physical activity include:
- Is the same intensity and type of activity good for everyone?
- Can we get to the point where we can identify and prescribe vigorous- intensity for some people and moderate-intensity for others, based on their biology?
Anything else women should keep in mind when they exercise to reduce risk?
First and foremost, be safe. Consult your doctor before you start any exercise program. If you are just getting started with some physical activity, it’s a good idea to take things slow and ease yourself into more intense activity. Regardless of your level of activity, you should pay attention to correct form and avoid overextending yourself. Overuse injuries can make it more difficult to stay active in the future!
Also, as research is ongoing, remember that guidelines may change over time. Overall it’s very unlikely that Human Health Services will ever tell you that exercise is bad for you…We know it’s good for us! We’re just trying to learn more about the how and why. So, go walk the dog – or join a marathon team!
Trainer Austin’s Tip:
Remember to TAKE YOUR RECOVERY DAYS to stay safe and prevent injury. This is something I personally struggle with, but having days to recover is not only great for your body but for your mind as well.