You probably wouldn’t believe me if I told you I had the magic pill to fight aging. Okay, okay you see right through me. Truth be told, there is no magic pill. But there is a proven way to reverse a slowing metabolism and decrease the likelihood of muscle loss as we get older: High intensity and strength training. It’s not a pill, a lotion, an injection, or even a class. It’s tried and true exercise in the form of sweat and effort.
Research shows that as we age, on average, individuals experience a 2-4% decline in their resting metabolic rates with each passing decade after age 25. That means that most people can look forward to an ever-diminishing rate from their mid-20s onward. Excited, right? Just keep paying attention. A person with an RMR of 1500 kcal at age 30 could potentially have an RMR of around 1400 kcal a decade later without changing anything. Think about it; by not changing anything about your routine or lifestyle, you could actually gain weight. After another 20 years you could see another 200 calorie drop!
With the metabolic loss comes muscle loss as well. On average, people lose about 5 lbs of lean muscle per decade between ages 25 – 65. In addition to the 300 kcal drop, they could lose upwards of 20lbs of lean body mass. It can be assumed that much of the metabolic loss is due in part to the decrease in muscle since our muscles are so metabolically active. Basically, less muscle, means more likelihood of a decreased metabolic rate (burning less calories and potentially gaining more weight). This decline suggests that it’s not “due to our age,” but rather a lifestyle decision or habit. What we may consider to be normal, may in fact, be reversible. We could at least have the ability to preserve and slow the rapid decline.
There is no question that different exercise intensities and methods affect our physiology differently. This is especially true with preserving our muscle and metabolism as we get older. Intense exercise prevents said muscle loss and preserves our resting metabolic rate. On the contrary, lower intensity, while great for physical activity and health, offers very little in terms of preventing muscle loss. The key is to focus on high intensity and include strength training.
So what exactly does “high intensity” mean? Strength training or resistance training, intervals, monostructural movements, conditioning, gymnastics, etc. are all high intensity activities. Examples of this are running, jumping rope, hill sprints, kettlebell exercises, plyometrics, climbing, cycling, rowing, weightlifting and so on. Basically, high intensity activity includes any demanding task that incorporates more than just a few muscle groups and performed in a manner that is close to your max heart rate.
But wait, there’s more. There is the glorious phenomenon of the “after-burn” or EPOC (Excess post-exercise oxygen consumption) or what I refer to as “free burn.” (It’s free because you don’t have to spend anything doing it). Your body has to work a little harder to return back to it’s normal state and in a big way, thus leading to an additional calorie burn, upwards of 10-25% more in the hours after exercise. When in comes to keeping your youth and maintaining a healthy body, metabolic preservation, muscle gain, and EPOC are all reasons to constantly seek out intense training sessions. Two to three sessions each week is all you need to drink from the fitness fountain of youth.
 Berardi, John. MD. The Essentials of Sport and Exercise Nutrition. (Precision Nutrition, 2014) 125.