When an individual exercises with the intention of improving physical fitness, he or she should be pushing the body beyond its comfort zone. It is only then that physiological adaptations take place in the body—that is, the body learns to cope better under physical stress. If you are too comfortable, adaptations don’t happen and the body maintains a status quo. The exercise load under which adaptation of the body takes place needs to be monitored to get the best results.
During physical activities, it’s a challenge to accurately assess the effect of training on the body.
A simple tool called heart rate monitor (HRM) allows you to better gauge the effectiveness of your exercise session by measuring your heart rate while exercising. It gives you an idea of the intensity your body is working at, and can be a good guide to whether to put your body under more or less strain. Most people would think that a device like HRM is only for professional athletes. But it has a role to play for all—an obese person on a weight-loss programme, a new fitness enthusiast, an amateur sportsperson, a new runner, and even cardiac patients on rehabilitation programmes post a bypass surgery.
Track it: A heart rate monitor can help you assess the effectiveness of your workout.
Even out of the sportspeople and sports enthusiasts who are hooked on to HRMs already, few are aware of what these monitors are capable of. Most are just interested in the current heart rate (HR), when they should be looking for heart rate variability (HRV). During two separate exercise sessions, your heart rate could have been the same during the activity, even though you felt that one was a lot harder than the other. The time interval between consecutive heart beats is not constant-this is called HRV, which is pretty much a unique physiological fingerprint for each individual. Even during rest, this interval between consecutive heart beats fluctuates with the breathing cycle. During exercise, HRV fluctuates depending on the intensity of the exercise. It can also indicate fitness levels and how economical your body is during an exercise. Effort put into doing any exercise varies with temperature, humidity, altitude, mood, hormonal status and medications, among other things.
Most people overtrain, which is the biggest cause for injuries and lack of results in proportion to the effort put in. The old adage of “training makes a man perfect” completely misses the point. It should be “correct training makes a person perfect”. HRV helps in suggesting well-timed rest—a well-rested body will produce a wider gap than a stressed out, overtrained body. A low HRV along with fast pulse means you have overtrained, so you need to rest longer. A high HRV reading along with a normal resting pulse gives you a signal to go and train hard as you have rested well.
Monitoring HRV is not only important during an exercise session, but also afterwards. It can help detect the additional amount of oxygen your body needs to recover after a training session (excess post-exercise oxygen consumption or EPOC), which till very recently could only be measured in laboratories—HRMs with HRV capability can indirectly measure EPOC based on the gap between consecutive heart beats. This helps us detect if the recovery is sufficient or not, as it indicates the impact of fatigue due to prior exercise sessions, hydration levels, stress and even degree of performance anxiety, nervousness or other external stressful influences.
One big misconception people have is that the longer the exercise session lasts, the better it is. The fact is, intensity of exercise is far more important than duration. This is confirmed by EPOC and HRV.
HRMs are a very good investment to get the best out of your exercise sessions, but look for ones with HRV and EPOC to get the best from the effort you put in. It’s high time we stopped “guessing” and started “assessing” what our bodies are telling us when we are doing these exercises.
Rajat Chauhan is a practitioner of sports and exercise medicine and musculoskeletal medicine, and CEO of Back 2 Fitness
Write to Rajat at firstname.lastname@example.org