Muscle Longevity: Strength at Any Age

If you had to name the organs medicine pays closest attention to, muscle probably wouldn't make your list. In Episode 35 of the Innersight Podcast, we sat down with biokineticist Hannes Swanepoel, who has spent 16 years specialising in injury rehabilitation, running, and cycling performance in Cape Town and Durbanville, to make the case that muscle deserves to be treated as seriously as any other organ system. Not just for athletes, but for anyone interested in a long, functional life.

Why Muscle Deserves Organ-Level Attention

The conversation opens with a simple but important reframe: muscle isn't just tissue that moves your skeleton around. It behaves, in many respects, like an endocrine organ. It's the body's primary storage site for glucose (as glycogen), it releases hormones and signalling molecules when it contracts, and its condition is directly tied to metabolic health, to the point where a muscle biopsy can reveal whether someone is developing type 2 diabetes. The more muscle you carry, the larger that metabolic "storage tank" becomes, and the more capacity your body has to actually use the fuel you take in, rather than letting it accumulate as a problem.

This connects strength training directly to outcomes people don't usually associate with the gym: lower all-cause mortality, reduced fall risk and better long-term metabolic regulation. It's also a direct continuation of a theme covered in Innersight's earlier episode on osteoporosis - bone needs mechanical loading from muscle to stay strong, so building muscle is, in a very literal sense, part of how you build bone.

How Much Muscle Do You Actually Need to Test?

A recurring, practical question in the episode is do you need a full professional assessment, or can you get a reasonable read on your own strength at home?

Hannes's honest answer is nuanced. The simplest starting point is entirely self-directed: look back over the last six weeks to three months and ask how much you're genuinely moving day to day, not formal exercise, just general activity, and how often you're pushing against resistance outside your comfort zone (carrying something heavy, walking up a hill, and so on). For most modern lifestyles, particularly desk-based jobs, that honest answer is often "not very much," which alone is a useful diagnostic.

Where a professional assessment becomes genuinely valuable is once you decide to actually start strength training. Unlike cardiovascular exercise, where simply walking more is a safe, low-risk starting point, strength training inherently requires working outside your comfort zone, which is exactly where old injuries, muscular imbalances and compensations tend to surface. Hannes's consistent advice: if you're new to resistance training, get a baseline assessment first, both to avoid injury and to make sure your program actually targets your specific weaknesses rather than a generic template.

The Muscle Loss Timeline

One statistic worth sitting with is this: muscle mass generally builds until around age 30, after which most people lose roughly 1% of muscle mass per year, a rate that accelerates to 3-4% per year once you reach your 70s. The encouraging part is that this trajectory is genuinely modifiable through training; it isn't a fixed decline you simply have to accept.

The practical implication is timing-related: someone starting strength training at 40 is working from a fundamentally different starting point, and with a longer runway to benefit than someone starting at 65 or 70 having never trained before, and the right program looks different for each.

How Strength Testing Actually Works

Hannes outlined the layered approach his practice uses to assess strength:

• Isometric strength testing - measuring how much force specific muscles (particularly those around the knee, hip, and shoulder) can generate against a fixed resistance over a few seconds.

• Grip strength - widely used in research as a general health proxy, though Hannes is clear that grip strength itself isn't the key variable; it's simply a convenient marker that correlates with broader upper-body strength and activity levels.

• Knee/leg strength - a particularly useful window into overall function, since stronger legs mean less fatigue during walking, which in turn supports more cardiovascular activity, better zone 2 training capacity, and improved day-to-day mobility.

Beyond generating a baseline, this kind of testing is also valuable for spotting asymmetries and long-standing compensations, for example, a meaningful strength difference between someone's left and right leg can sometimes be traced back to an old injury (a bout of lower back pain years earlier, say) that quietly changed how someone walked for months, allowing a deficit to develop and persist long after the original issue resolved.

Strength Is a "Use It or Lose It" System - But It's Also About Coordination

A key distinction raised in the conversation is that raw muscular strength and the ability to actually use that strength in real-world movement are two different things. Hannes uses a memorable analogy - a hosepipe and a steel pipe are both strong and hard to break, but the steel pipe is far easier to drive into the ground, because it doesn't bend or waste energy the way the hosepipe does under the same force. In the body, that "steel pipe" quality comes from stability and neuromuscular coordination, not raw strength alone. This is why the strongest person in the gym on a leg press isn't necessarily the fastest runner; strength has to be paired with the coordination to express it efficiently in a real movement pattern.

This is also why Hannes's programming typically progresses from isolated, machine-based exercises (useful for building raw strength safely, especially around an injury) toward free-weight, multi-joint movements like squats, lunges, and, when technique genuinely supports it, deadlifts, which demand far more coordination and better mirror real-world movement demands.

Strength Training Can Also Improve Flexibility and Stability

Somewhat counterintuitively, Hannes noted that properly performed strength training - moving through a full, controlled range of motion under load - can be a more effective way to restore flexibility than static stretching alone. A classic example from sports rehab: recovering hamstring or calf length after a strain often responds better to controlled, loaded movements like a stiff-leg Romanian deadlift (taken to end-range within a safe capacity) than to isolated stretching.

Similarly, certain strength exercises such as single-leg deadlifts and single-leg squats simultaneously train stability, since they demand balance and control throughout the movement. In practice, this means well-chosen strength work often delivers benefits across multiple "pillars" of fitness at once, rather than requiring entirely separate flexibility or stability specific sessions.

Strength, Power, and Why They're Not the Same Thing

The conversation drew an important distinction between strength and power. Strength is the maximum force a muscle can produce; power is how quickly that force can be produced, and the two don't always track together. A useful example: during running, each foot spends only around 300 milliseconds in contact with the ground. Someone can have very strong legs in the gym but still only access a small fraction of that strength if they can't generate force quickly enough within that narrow window.

This matters because power, unlike raw strength, tends to decline notably with age, largely tied to the loss of fast-twitch (type II) muscle fibres. Hannes's typical approach is sequential: first build a "big engine" through slower, heavier strength work, then, once a solid strength base exists, layer in faster, more explosive movements (like a lighter, quicker sit-to-stand rather than a heavy, slow squat) to convert that raw strength into usable power - with these explosive elements introduced later, once form and strength are well established, given the higher technical demand and injury risk.

Building Muscle vs. Building Strength — And Why Women Shouldn't Fear the Weights Room

An important myth addressed directly is that many women avoid resistance training out of a fear of "getting too big" or overly muscular. Hannes was clear that building significant muscle mass is genuinely difficult and requires a very specific, high-volume training approach - it isn't an accidental side effect of general strength training. The longevity research underpinning most of this conversation (grip strength, functional strength, fall risk) has little to do with muscle size and everything to do with strength itself, a distinction reinforced by looking at elite endurance athletes (ultra-trail runners, top-tier triathletes), who are often lean rather than bulky, yet remarkably strong in the gym once you look at what their programs actually include.

For runners and cyclists specifically, research cited in the conversation suggests a genuinely modest time investment - as little as 60-90 minutes of strength training per week, split across two sessions - can meaningfully improve running economy, without adding significant muscle bulk, since endurance-focused strength programs typically avoid training to complete muscular failure the way hypertrophy-focused programs do.

Getting the Dosage Right

For anyone starting resistance training, Hannes offered concrete, practical guidance to avoid the two most common mistakes - being too conservative (and seeing no benefit) or pushing too hard, too soon (and getting injured):

• Aim for roughly 6 to 15 repetitions per set, working to around 80-90% of effort - leaving a small buffer of 1-3 repetitions "in reserve" rather than training to complete failure, especially when starting out.

• The last few repetitions of a set - the ones performed as the muscle approaches fatigue are doing most of the work in terms of building strength; simply completing many easy repetitions with too-light weight delivers limited benefit.

• If you can comfortably exceed 15 reps without reaching meaningful fatigue, it's time to increase the load; if you're struggling to reach even 6, the load is likely too heavy.

For more experienced trainees, a 10-repetition maximum test (commonly using squats or leg press for the lower body, and bench press for the upper body) offers a way to estimate a true one-repetition maximum and benchmark against age- and gender-specific norms, but this is a later-stage tool, not a starting point.

Recovery, Nutrition, and Why You Don't Get Stronger During Exercise

One of the more clarifying points in the episode: strength training itself doesn't make you stronger, it's the recovery afterward that does. Lifting weights temporarily breaks the muscle down slightly, dropping performance below baseline; the actual adaptation happens in the hours and days that follow, driven by adequate protein, carbohydrate, and critically sleep, which Hannes described as the single best recovery tool available.

On protein specifically: most people don't struggle with total calorie intake, but do struggle to hit adequate protein targets (commonly cited around 2g per kilogram of bodyweight for those actively strength training) - a single steak or egg contains far less usable protein than people tend to assume. Timing matters somewhat (getting protein in within roughly 90 minutes after training appears modestly advantageous), but consistency matters more than precision. Protein absorption also becomes less efficient with age, which is part of why supplementation becomes more commonly necessary from the 50s onward, even for people who managed perfectly well on food alone earlier in life.

Hormonal changes such as declining testosterone in men and menopause in women, also affect the body's ability to build and maintain muscle, which is part of why hormone optimisation (including HRT where appropriate) is increasingly discussed as a legitimate, complementary piece of this picture rather than something to avoid.

Software Before Hardware

A phrase that captures much of the episode's underlying philosophy: build the "software" before the "hardware." Picking up a weight and progressively loading a muscle is, in Hannes's words, the relatively easy part. Rebuilding the neuromuscular coordination and stability that often erode after an injury, a long sedentary period, or simply years of disuse - that's where professional guidance tends to matter most, and where people frequently need patience.

Early-stage rehabilitation work can feel unglamorous or pointless in the moment (balancing on an unstable surface, holding an awkward position), but it's precisely this "boring" foundational work that determines whether later strength training actually translates into real-world function, rather than simply building strength that the body can't safely or efficiently express.

The Bottom Line

Across this conversation, a consistent thread ties back to nearly everything Innersight covers: something is almost always better than nothing, but getting real benefit safely usually requires understanding where you're actually starting from.

Muscle strength isn't just about aesthetics or gym performance; it's a legitimate, measurable pillar of metabolic health, fall prevention, bone density and long-term independence. As Hannes put it plainly by the end of the episode: the health benefit lies in being stronger, not in how that strength happens to look.

Watch this episode on our Youtube channel: https://youtu.be/8ROSyB7Kps4

For more information, you can contact Hannes at the following website: https://www.runningsmart.co.za/

#Longevity #StrengthTraining #HealthyAging #MuscleHealth #FunctionalFitness #TrainSmart #InjuryPrevention #ActiveAging #MoveBetter #FitnessEducation #HealthPodcast #Wellness #Mobility #LiveBetter #Biokinetics #Biokineticist #Innersight

This blog post is not intended as a substitute for the advice of your healthcare provider. No doctor-patient relationship is formed through this content - it is provided for general informational purposes only.