In the past, conventional wisdom stated that if a person wanted to lose weight, they should eat less and run more. The math makes perfect sense on that approach. However, whether due to modern science or an aversion to cardio, many strength trainers have stated that cardio not required to lose weight and that weight training alone is more than sufficient. To understand which side of this argument got it right, it is important to understand some of the physiological effects of both exercise modes on the human body.
Physical Effects of Cardiovascular Training
No one, even the strength training adherents, would argue that there are no health benefits to cardiovascular exercise. According to most doctors, these health benefits are so significant that everyone should seek them out, regardless of their current physical health. For example, people who engage in regular cardiovascular training benefit from a more efficient heart. This allows for more oxygen intake during periods of activity, and a lower resting heart rate. Cardio also allows the participant to develop lower blood pressure levels and lower cholesterol in their blood.
However, when engaging in cardiovascular training, the athlete enters a state of glucose depletion. This makes sense because glucose often burned to fuel the energy needs of a body in motion. After a cardio session, people often require significant amounts of carbohydrate intake to replenish these reserves. Also, when effort exceeds available energy, cardiovascular exercise can inhibit muscle growth.
Physical Effects of Weight Training
When athletes engage in weight training, a new physiological state result. Since there is less of a prolonged energy expenditure, weight training does not deplete the body’s glucose reserves. Instead, the activity causes an increased need for protein to repair damaged muscle tissue. Also, much like cardiovascular training improves the functioning of the heart, weight training improves the central nervous system response and muscle functioning.
Because fewer calories burned during weight training, weight loss is not an immediate byproduct. That said, additional muscle mass allows for a higher resting metabolic rate. This means that the body will burn more calories at all times, regardless of activity level. While there is a debate about the actual additional calorie expenditure that muscle mass provides, everyone agrees that this phenomenon exists. Furthermore, additional muscle changes the body’s response to insulin, which can have a profound impact on the way fat is manufactured and stored.
Cardiovascular Exercise, Weight Training, and Weight Loss
Obviously, cardiovascular exercise has a larger upfront calorie cost and therefore burns more fat in the short term. However, the refueling state that the body enters often seen as a detriment to muscle growth. On the other hand, weight training builds the necessary muscle to maintain a lean physique. But weight training does not burn enough calories by itself to effectively shed fat efficiently. What, then, is the proper course of action for an aspiring athlete?
Not surprisingly, the answer is both. Cycling weight training sessions with cardio training appear to have the best effect. On weight training days, athletes would do well to increase their calorie intake, particularly through the protein. On cardio days, a calorie deficit should be combined with light cardiovascular activity and ample water. This allows the athlete to combine the growth state created by weight training with the weight loss state achieved through cardiovascular exercise.