Strength First: Why Muscle Mass Is Your Most Important Health Asset After 35

Estimated read time: 6 minutes

Mark runs four days a week. He has done for years. He tracks his kilometres, watches his heart rate, and eats reasonably well. By most measures, he is an active 42-year-old. But his weight has not shifted in three years and in fact, he’s developing love handles and losing his bicep definition, and is noticing his energy crashes by mid-afternoon. Last month he pulled something in his lower back getting out of a car.

Sarah is 38 and returning to sport after a few years away raising kids and running a career. She was always fit. She did yoga, walked daily, and kept her cardio up. Now she is back training and feeling like she is starting from scratch. She tires faster than she expects, her joints ache in ways they never used to, and she cannot figure out why her body feels so different.

Mark and Sarah have different lives, different goals, and different training histories. But they share one thing: they are both running the wrong program for where they are now.

And the reason is almost always the same. They have been told, directly or indirectly, that cardio is the answer.

Start with running, beating the pavement. Start with 3km, build up to 5, work up to doing 10km on the weekend. That movement is good, more movement is better, and as long as your heart rate is up, you are doing the right thing. It is one of the most widespread and well-meaning pieces of health advice out there.

It is also, past the age of 35, quietly incomplete.

The thing nobody tells you about getting older

From your mid-30's onward, your body begins to lose muscle mass. Not dramatically at first, but consistently. The clinical term is sarcopenia, and without deliberate intervention, most adults lose between 3-5% of their muscle mass per decade. The rate accelerates after 60, but the process starts well before most people notice it.

Here is why that matters: muscle is not just about how you look or how strong you feel in the gym.

• Muscle tissue is your primary site for glucose metabolism. This means it regulates your blood sugar, decreasing the chance of developing Type II diabetes (and even reversing Type II diabetes!). Additionally, the more muscle mass you have, the more calories you will burn at rest.

• Muscle supports your joints. This means that each step you take and jump you make can be absorbed by your muscles as opposed to your joints. Failing to protect them from wear and tear leads to chronic pain and injury.

• Muscle is directly connected to your hormonal health. Your bone density, your metabolic rate, and your capacity to recover from illness, surgery, or injury.

Muscle mass is, quite literally, a biological health asset. And like any asset, if you are not actively building and maintaining it, you are losing it.

Cardio does a lot of important things. It strengthens your cardiovascular system, your heart, supports mental health, and has real benefits for longevity. But it does not build muscle. In fact, chronic cardio without adequate strength training can actually accelerate muscle loss, particularly when combined with under-eating or high stress. The body is efficient. If you are not giving it a reason to maintain muscle, it won’t do so by itself.

Why the shift from cardio-first to strength-first changes everything

Strength training after 35 is not about aesthetics, though improvements in body composition are a natural by-product. It is about preserving the physical infrastructure that everything else in your life runs on.

When you lift consistently, you stimulate muscle protein synthesis. You signal to your body that maintaining and building muscle tissue is a biological priority. This has a cascade effect. Your resting metabolic rate improves because muscle burns more energy than fat at rest. Your hormonal profile shifts, with better insulin sensitivity and, for women in particular, meaningful support through perimenopause and beyond. Your joints become more stable because the muscles surrounding them are stronger. Your bone density is maintained through the mechanical load of resistance training in a way that low-impact cardio cannot replicate.

For the executives, professionals, and returning athletes reading this, there are two other benefits that rarely get enough attention: resilience and longevity of performance.

Resilience means your body can absorb stress, recover from effort, and bounce back from the unexpected. A strong body with good muscle mass is less likely to be derailed by a minor injury, a stressful travel week, or a season of disrupted sleep. It has reserves to draw on. Longevity of performance means you can keep doing the things you love, whether that is boxing, running, playing sport with your kids, or competing recreationally, at a high level and without constant breakdown.

How training needs to shift after 35

The principle is straightforward: strength comes first. This does not mean abandoning cardio. It means restructuring your week so that your primary training stimulus is resistance-based, and your cardiovascular work is programmed around that foundation, not instead of it.

For someone training 3-5 days per week, this typically looks like 2-3 dedicated strength sessions built around compound movements: squats, deadlifts, presses, rows, carries.

These are the movements that recruit the most muscle, generate the most hormonal response, and deliver the most return for the time invested.

Cardio is then layered in at an intensity and volume that supports recovery rather than competes with it.

Recovery itself becomes a training variable, not an afterthought. Sleep, protein intake, and managing training load across the week are not optional extras. They are the conditions under which adaptation actually happens. A 38-year-old woman or a 42-year-old man cannot train like they are 22 or even 32 and expect the same results. But they can train smarter, more intentionally, and with a better understanding of what their body actually needs.

The sport-specific and movement-quality dimension

For those who train for sport, whether that is recreational or for competition, strength training does not compete with sport performance. It underpins it.

The ability to generate force, absorb impact, decelerate, and change direction all depend on a base of muscular strength. Athletes who neglect strength work eventually find a ceiling on their sport performance, and it tends to arrive in the form of injury.

Mobility and movement quality matter here too. Strength training, done well, improves range of motion and movement efficiency. It is not the enemy of flexibility. In fact, loaded movement through full range of motion - think Romanian deadlifts, goblet squats, front squats, back squats, overhead presses, dead hangs - is one of the most effective ways to build functional mobility over time. The athlete who lifts intelligently tends to move better, not worse.

What this looks like in practice

You do not need to become a powerlifter and you certainly won’t become a bodybuilder.

You do not need to spend hours doing resistance training, whether at home or at the gym. What you need is a consistent, well-structured program that prioritises lifting 2-3 times per week, builds progressively over time, and treats recovery as seriously as the training itself.

For Mark, that means keeping one or two of his runs but reducing the volume, and replacing his other cardio days with two strength sessions focused on the movements his body has been neglecting. For Sarah, it means building a strength foundation before returning to high-intensity sport, so her joints and connective tissue are ready to handle the demand.

The shift is not complicated. But it does require someone to help you structure it properly, to make sure the program fits your goals, your schedule, and where your body actually is right now.

The bottom line

Cardio is not the enemy. But if strength training is not central to your program after 35, you are leaving your most important health asset unattended.

Muscle mass protects you, performs for you, and keeps you doing the things that matter. The sooner you start building it intentionally, the more you have to work with as the decades continue.

If you are ready to stop guessing and start training with a purpose, this is exactly what we work with my clients. Whether that be through private coaching or through 8-Weeks to Strong - my approach is designed for people who are serious about their health and want a coach who understands both the science and the lived experience of training past 35.

Book a free strategy call and let us look at what your training actually needs.

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