Before we get into today's episode, if you want to actually improve your body composition and are sick of random workouts that just wear you down and burn you out, that's exactly why I build Evolo. Evolo is science-backed strength training designed to help you build muscle, improve body composition, and feel better in your body without beating yourself up or living in the gym. You can try Evolo now for two weeks free if you visit evolofitness.com. Welcome to Fitness Rewired on the Dr. Shannon Show, a nine-episode capsule designed to close the gap between fitness culture and exercise science so you can see higher return on your effort and finally feel like you're doing enough. Many fitness beliefs come from marketing and tradition and don't align with current evidence. When you learn the truth, you can rewire your thoughts around fitness. That shift leads to higher quality actions, better results, and health you can actually sustain. I'm your host, Shannon Richie. Welcome to the show. Heavy lifting. I will keep this episode really brief, but hopefully it's empowering because you might have seen experts saying that heavy lifting is the only way, but if that's not something you want to do, this episode is for you. I want to explain what the science currently shows about how heavy you have to lift to build muscle and strength, and to be clear, this information applies to both men and women of all ages, including women in peri and postmenopause. Women are getting told that they have to do heavy squats and heavy deadlifts and heavy presses to see muscle growth and strength, and that certainly works, but it's not the only way. Not enough women are lifting weights, so we need to give them the correct information so that we can make it more accessible. So here's what the literature currently shows in all age groups in men and women. You can lift heavy or relatively light and see the same muscle growth. You can build strength and change your body composition with lighter weights or heavier weights. You can do compound lifts like squats, or you can do more isolated lifts like a bicep curl or a combination of both. There is a wide range of reps and exercises that will work. I'll give you some reasons for why you may choose one rep scheme over another in a moment, but it mostly comes down to preference, which is great news because when you prefer your workouts, you're more likely to stay consistent. So although light weights work just as well, too light, like some high rep workouts like bar or some barbell type lifting classes, they don't do very much. So let's put some guardrails around this and define what heavy or light actually means in the scientific literature. So heavy loads are weights that you can lift for about six reps or less before your form starts to break down and you get to failure. Heavy loads feel challenging from the very first rep and require full focus. The rep scheme typically won't burn as much as moderate weights or higher weights, but the burn is not required for muscle growth. Moderate loads are weights that you can lift for about six to 12 reps. They feel a bit challenging at first. You're well aware that you couldn't just keep going all day, but the challenge rapidly increases as you pass that 10 to 12-ish rep mark and you get close to failure after about 12, maybe 15 reps. Moderate loads may burn a bit more as you approach the end of your set, but it's clear that you're stopping the set due to mechanical muscle failure, not due to the discomfort of the burn. That's how you know you're in that moderate range. Light loads are weights you can lift for roughly 12 to 30-ish reps. They don't feel heavy early on, but if taken close to failure, they can still create muscle growth. Light loads will accumulate a lot more metabolic stress or that burn, which makes people think they're more effective than heavier loads since the sensation in the muscle is much higher. But again, the burn is not causing muscle growth. Approaching muscular failure is causing muscle growth. Check out episode number four in this capsule to learn more about the burn. Super light loads are weights you can lift for more than 30 reps. They feel very easy at first. They burn after a while, and most of these are building muscular endurance, but not substantial muscle growth or strength comes from super light loads. They're not the best use of your time. This is typically what you're doing in group fitness classes, again, like the barbell lifting classes, some bar classes, some Pilates classes, things like that. So that's heavy, moderate light and super light loads. We know that heavy, moderate, and light loads can all build muscle, but when should you choose heavy, moderate, or light? As long as you take them to failure or one to three reps, shy of failure, heavy, moderate, and light loads under 30 reps will be equally effective for muscle growth on paper. If you are newer to lifting, staying in the lighter loads is a really great place to start. It may feel lower risk, more approachable. You can get the movement pattern down and start to sense what it feels like to train close to failure. Light loads can be great, but here are a couple of reasons why you would want to choose something heavier or more moderate. So number one, lighter loads typically just take longer because you're doing more reps. Number two, you may find that you're limited by the fatigue or burn, not by true muscular failure. It gets harder to distinguish if you're stopping the set because of the burn or if you're stopping because of true failure. This is why moderate or heavier loads are more quote unquote foolproof as you get used to lifting weights because you accumulate less metabolic stress and tend to more reliably get close to true muscular failure. As you train, you may feel like you gravitate more towards heavier and heavier loads and they do have their advantages, but the most important part is that you're consistently training close to failure in under 30 reps, regardless of your preferred rep scheme. So that's a quick breakdown of loads that build muscle and strength. But remember, heavy and light is relative. It's relative to the individual and it's relative to the exercise. For example, a 25 pound dumbbell curl, bicep curl, feels heavy to me, but that might be light to my husband. That same 25 pounds that feels heavy for a bicep curl will feel light for a hip thrust for me. So the truth is you need a variety of dumbbells and a variety of loads for different lifts. You can't just use the same set of dumbbells and expect to build muscle across your whole body. A 10 pound weight may seem heavy if you're used to three pound weights in your group fitness classes. And although that may seem heavy relative to what you're used to, it still may not be heavy enough for most of your lifts. So no, you don't need barbells and super heavy weights, but you do need sufficient load. A really easy way to know if any exercise is challenging enough and if you have the right weight is just to do as many reps as you physically can with the weight that you've selected. If you find yourself easily passing 20 reps, you could probably get to 30, no problem, and that means it's too light. So the bottom line is you should not be able to do more than about 30 reps. If you can, it's too light, go a little heavier, but super heavy sets where you could only do maybe like four reps are not necessary either. I personally prefer the eight to 12 rep range for most of my lifts, but it definitely depends on the exercise. For bicep curls, for example, I like a six rep set because it's a very simple exercise and honestly, I just like to get them over with. For legs, I like something a little bit lighter, more of that moderate range. I love like a 15 rep set for legs, but you experiment and find the rep range that you prefer knowing that it can be different for different exercises and it can change over time. You have so many options and the people who are preaching that it has to be super heavy are not aligned with the current literature. This goes for peri and postmenopause as well. So that's lifting heavy. Tomorrow we will be talking about soreness, what it means and what it doesn't mean about your training stimulus. I'll see you then.
