Ask a physiologist what happens to muscle as we age and they will tell you about sarcopenia — the progressive loss of muscle mass and strength. Fair enough.
But there is a second, faster decline underneath it that almost nobody measures, and it is the one that determines whether you catch yourself when you trip.
Muscle power — force multiplied by velocity, or how much force you can produce quickly — declines substantially faster than muscle strength. Where maximal strength might fall around 1 to 2% per year after 50, power falls at roughly double that rate.
By 75, a person may retain 70% of the strength they had at 50 but only half the power.
Why the difference exists
Because ageing does not affect all muscle fibres equally.
Type II fibres — the fast, powerful, high-force fibres — atrophy preferentially with age and disuse. Type I fibres, the slow endurance fibres, are far better preserved.
Alongside this, the nervous system changes: motor unit numbers decline, remaining motor units are remodelled, and the rate at which the nervous system can recruit and fire motor units slows. Rate of force development — how fast you can turn muscle on — deteriorates.
The result is a person who can still lift a reasonable weight given time, but cannot generate force in a hurry.
The 400 milliseconds that matter
Here is why this is a longevity issue rather than an athletic one.
When you trip, the sequence of events available to you is measured in fractions of a second. You have roughly 200 to 400 milliseconds to detect the perturbation, plan a response, and get a foot out in front of your falling centre of mass.
Maximal strength is largely irrelevant in that window. You cannot reach maximal force in 300 milliseconds — it takes most people considerably longer than that. What matters is rate of force development: how much force you can produce in the first fraction of a second.
That is power. And it is why studies consistently find that lower limb power predicts functional performance and fall risk better than maximal strength does.
The same applies to getting out of a chair, climbing a step, crossing a road before the lights change, and recovering from a stumble on an uneven track at Tamborine Mountain.
The training mistake
Most strength programs for older adults are slow. Deliberately, carefully slow — often with an instruction to “control the movement” throughout.
Controlled tempo is appropriate for learning a pattern and for building tissue capacity. But if every repetition of every exercise for five years is performed slowly, you are training exclusively in a velocity range that does not transfer to the moment you need it.
You will get stronger. You will not get faster. And falls happen fast.
What power training looks like at 70
It is not Olympic weightlifting. It is not jumping off boxes. It is far more sensible than people imagine.
The principle: moderate load, maximal intended concentric velocity, controlled lowering.
Practically:
- Sit-to-stand for speed. Stand up as fast as you safely can, sit down slowly. Progressed by lowering the chair or adding load.
- Leg press or squat with fast concentric. Typically 40 to 60% of maximum, pushed explosively, lowered under control.
- Step-ups performed with intent. Drive up quickly, lower slowly.
- Medicine ball throws. Chest passes and overhead throws train upper body rate of force development safely.
- Fast band-resisted pushes and pulls.
- Reactive stepping drills. Deliberately perturbed balance with rapid step recovery — the closest thing to rehearsing a real trip.
Two sessions a week, on top of — not instead of — heavier strength work.
The safety question
Is it safe to ask a 75-year-old to move fast?
Power training in older adults, including frail older adults, has been studied extensively and has a good safety profile when appropriately prescribed and supervised. The load is moderate; it is the intent that is maximal.
The genuine risk is the opposite: an older adult with no capacity to generate force quickly, who trips on a garden step and has no response available.
Building the base first
Power sits on top of strength. Someone who cannot complete five good sit-to-stands is not ready to do them explosively.
The sequence we use at Longevity Physio Studio in Eagle Heights is: establish movement competence, build tissue capacity and maximal strength, then layer velocity on top. Skipping to the third stage is where people get hurt.
How we measure it
- 30-second sit-to-stand — a practical proxy for lower limb power
- Five times sit-to-stand, timed — sensitive to change
- Stair climb power test — timed ascent, adjusted for body mass
- Grip strength — whole-body strength proxy
- Timed Up and Go
- Single-leg stance and reactive step testing
Repeat them every twelve weeks and you have an objective picture of whether your program is working or whether you are simply attending.
Book a strength and power assessment
If you are over 60 and doing steady, careful exercise, you may be training only half of what determines your function over the next twenty years.
Longevity Physio Studio, Eagle Heights, Mt Tamborine — serving Tamborine Mountain, North Tamborine, Canungra and the Gold Coast hinterland. Book an assessment.
