You know what I never get? The one-dimensional exerciser. You know who I’m talking about–the buffed guy who never does cardio; or the panting and sweaty guy who does an hour on the treadmill (get off, man–people are waiting!) and nothing else. Even so, most people have the sense that they’ve gotta mix it up from time to time. But now, my friends, we’ve got proof.
A recent study published in the Journal of Applied Physiology looked at athletes who participated solely in one fitness activity–either endurance or strength training–and found that people who do cardiovascular exercise (endurance training) have an increase in size of both their right and left heart ventricles, while those who do strength training have excessive growth in their left ventricle only. Additionally, the ability of the left ventricle to fully relax between beats–the diastolic function–is enhanced in endurance athletes, while it worsens in strength trainers.
The heart ventricles pump blood away from the heart. The right ventricle pumps blood to the lungs and the left ventricle pumps blood to the rest of the body. It doesn’t take a rocket surgeon, then, to figure out why cardiovascular training increases growth in both ventricles–cardio pumps blood to the lungs as well as the working muscles of the body. And it’s not brain science understanding how strength training increases growth in the left ventricle excessively. Pumping iron requires massive amounts of blood moved to the working muscles. Heart muscle, like any other muscle, increases in girth when exercised. Pumping iron=pumping blood=buffed heart. That’s a heavy workload for the left ventricle to supply the muscles of the body all by its lonesome–but it does.
Unfortunately, an enlarged left ventricle can present a problem. It’s called left ventricular hypertrophy and can lead to things like shortness of breath, chest pain, sensation of rapid, fluttering or pounding heartbeats (palpitations), dizziness, fainting, or rapid exhaustion with physical activity. Therefore, it’s probably not a good idea to neglect your cardiovascular training. If you read my book, The Six Keys to Optimal Health, you’ll see how all three pillars of exercise–resistance training, cardiovascular training and stretching–work together to enhance each other. So you’ve really got to do each one in balance.
Some people think that if they just do their weight training at a quick pace then they’re getting their cardio in. Uh, no, sorry. Cardio is cardio. Try this. Moderately paced and continuous aerobic exercise (weight training is anaerobic) that makes you sweat. That’s it. That’s cardio. It’s not window shopping, walking through the parking garage to your car, or resting for only one minute instead of two between sets at the gym. Uh uh. Nope. Gotta keep moving for 15, 20, or 30 minutes. And if you do it regularly, you’ll gain strength, balance, and endurance in your muscles, lungs, and heart. Now ain’t that worth the added sweat?