One of the most common things I hear when talking to people who are new to exercise (and sometimes lifelong gym members) is, “I don’t want to get big and bulky”. This is an understandable concern for those who prefer to not have the aesthetic look of Arnold Schwartzenagger. However, It’s important to understand that bodybuilders and strength enthusiasts spend a lifetime trying to achieve cartoon-like muscularity. You won’t just wake up one day as the Incredible Hulk. Based on the majority of people’s goals (tone up, less body fat, strength, balance, and mobility) you actually will want to build more muscle. Let me explain why: research has demonstrated that after about the age of 25 Resting Metabolic Rate (RMR) starts to decrease by 2-4% each decade. That means that by age 55 your RMR will likely have decreased by 6-12% or from 2000 calories/day to perhaps as low as 1760. If your nutrition or activity levels don’t change this will lead to weight gain. This is likely at least a significant contributor to why on average Americans gain 3lbs every 5 years.
Interestingly we also tend to lose about 5lbs of lean mass (which is slightly more metabolically active than fat) per decade after the age of 25. This is no coincidence. With less muscle, our metabolism slows, we have less strength so what used to seem easy and effortless is now a struggle, so we simply start avoiding these tasks, and tend to gain weight as fat. We start to move less because it’s harder, which leads to more muscle loss, slower metabolism, and so forth. It’s a vicious cycle. This cycle happens so slowly that many don’t see it until it’s very hard to reverse. You become more fat (less toned), lose strength (and power), and can’t move as well. Here is the good news. It’s all largely preventable! In many cases it can also be reversed. Resistance training with the goal of hypertrophy (muscle growth) and strength gives your muscles reason to grow, or at very least not atrophy and whither away. Nutrition plays a vital role in this as well as you need adequate nutrients (particularly protein) in order to build and repair that muscle. Holding onto and increasing your muscle is a great way to get “toned,” but it is also great for ensuring long term fitness goal success. Step off the treadmill, pick up something heavy, eat a steak, and give your metabolic rate a fighting chance as you age.