Sometimes when it comes to cardiovascular exercise, less is more.
Recently, we’ve seen more studies and reviews on the potential dangers of aerobic exercise, along with a growing consensus that excessive cardio can be detrimental to long-term health and fitness.
While most Canadians would do well to exercise more, there is growing evidence that there is such a thing as too much cardio. What we do know is that frequent long bouts of endurance exercise can be a stressor on the body, releasing the stress hormone cortisol, leading to inflammation, joint problems, and increased risk of heart problems such as irregular heartbeat.
A recent Swedish-led study published in the European Heart Journal found that top long distance cross-country skiers are at increased risk of heart problems such as arrhythmia.
The relatively large study examined nearly 53,000 elite male skiers and found that despite being extremely fit, the endurance athletes were at higher risk of certain heart conditions. The study’s authors are quick to remind that this does not mean that we shouldn’t exercise.
So how much is too much? The key is recovery. In order to elicit a training response we need to stress the body somewhat, but problems can occur when we no longer have the ability recover from the stress we put on our bodies. This can happen if we train for too long at too high an intensity, or if we train too frequently, not allowing the body to recover between sessions.
A good way to get around this is to keep the intensity low for longer bouts of aerobic activity, sticking to walking or hiking or playing leisurely outside, such that these sessions are restorative rather than stressing. On the other hand, keep high intensity sessions shorter, focusing on interval training or sprints.
If lots of cardio is not ideal for our health, what should we be doing instead? The most important physical skills as we grow older are joint mobility and flexibility, along with strength, muscle mass and cognitive function. Another recent study give us a clue, suggesting that yoga improves brain function more than cardiovascular exercise.
The research, conducted at the University of Illinois and reported in the Journal of Physical Activity & Health, concluded that the participants’ cognitive performance was significantly improved after yoga, compared to after aerobic exercise or to the baseline.
My recommendation: high intensity exercise a few times per week, including strength training and sprints, walk or hike a few times a week and yoga or stretching a few times a week.
Tania Tetrault Vrga is owner and head trainer at CrossFit Winnipeg. Send questions to her at www.crossfitwinnipeg.com