Hey, all! I wanted to give a quick update about the exercise capacity testing I did over the weekend. In college, I majored in exercise physiology, and as a physical therapist, I apply Ex Phys principles daily, so it was important for me to have an idea of my baseline physical fitness and my post-treatment fitness so I can work my way back up again.
*NOTE: If you don’t feel like reading, catch my video at the end of this post!
What is exercise capacity testing?
Exercise capacity testing is used to determine cardiorespiratory fitness. The test that I used for myself is a cardiac “stress test” which is a graded treadmill test that is used to estimate peak exercise tolerance (VO2max). I used the Bruce protocol which gradually increases the speed and incline of walking (exercise intensity) over 3-minute intervals.
Because I was unable to complete a “true VO2max” test, I used an equation to estimate my peak exercise tolerance which is the best I can do without lots of fancy equipment!
Why complete an exercise capacity test?
Cancer treatment can result in significant physical decline, and some types of chemotherapy can affect the heart function (both in the short or long-term). I feel like every person undergoing cancer treatment can benefit from a supervised cardiovascular testing to guide their aerobic training as they complete cancer treatment and as they recover when treatment is done.
Personally, I wanted to know my baseline and post-treatment measures in order to better guide my usual aerobic exercise training program. Because my primary goal during cancer treatment is to heal my body, I do not want to overexercise and delay the healing process. I have continued to exercise at a lower intensity throughout chemotherapy (primarily walking 3-4 days per week for 20-30+ minutes and body weight resistance training) and I know it has helped me reduce fatigue and bone/muscle pain, improved my mental health, and helped manage weight changes and lymphatic drainage.
What does the treadmill test measure?
For the treadmill test, I kept track of:
- Resting heart rate (HR) – normal range is 60-100 beats per minute
- Interval HR – should gradually increase as exercise intensity increases
- Resting blood pressure (BP) – normal is <120/<80 mmHg
- Interval BP – should stay the same or increase slightly as exercise intensity increases
- Rate of Perceived Exertion (RPE) – subjective measure of how hard someone is exercising – should increase as exercise intensity increases
- Dyspnea Scale – subjective measure of shortness of breath during exercise – should increase as exercise intensity increases
What were my results so far?
Despite maintaining a consistent aerobic program, I still saw a significant decline in my estimated VO2max. Prior to treatment, my estimated VO2max was 44 mL/kg/min, and at two weeks post-chemotherapy, my estimated VO2max is 31 mL/kg/min. I expected a decline for two reasons: 1) my aerobic training volume decreased significantly – no spin class during chemo & COVID (booooo!) and 2) chemotherapy and the cancer itself cause general changes in our body’s physiology that we can’t 100% control.
I noticed that my resting HR increased during chemotherapy (which my oncologist said is normal), but this likely decreases my exercise tolerance as well. I actually stopped my post-chemo test a bit early because my HR was getting so high!
Like I said, I did a pre-treatment test, now a post-chemo test, and I’ll continue to repeat the testing every 3 months over the next year or so to make sure I am able to get back to (or at least close to) my baseline and also to be sure I can bring up any concerns to my doctor should they arise.
How can you get an exercise capacity test done?
Not all physical therapists are alike in this case, and many do not perform exercise capacity testing, however certain PT’s or clinics in your area may offer these tests in a modified capacity (like I did). Call ahead to some PT clinics in the area to see if they can offer these services to you and ask your oncologist for a referral before you begin treatment. If you’re having difficulty finding a physical therapy clinic that offers this service, you may be able to work with an exercise physiologist or cardiac rehab specialist who does similar stress tests at local hospitals.
An important thing to note: I used the Bruce protocol initially because I was unaware that there has been a specific protocol developed for the oncology population through the University of Northern Colorado Cancer Rehabilitation Institute. They have also developed normative VO2 values for the oncology population as well, so be sure that whoever does your testing is aware of this option!
Check out the video below for a little more detail on my results & the testing process!
I’ll see my surgeon tomorrow to make a plan for surgery & determine what some of the next steps may be – wish me luck! Hope you all have a great week & that you’re taking care of yourself with all of the election energy in the air — Don’t forget to wash your hands & social distance, my friends!