Read time: 4 minutes

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It’s no surprise a good reason to exercise is better health and fitness.

But there’s more to it than that.

You see, there are times when exercise simply isn’t a possibility.

Because at some stage we ALL succumb to periods of:

• Injury
• Illness
• Or hospitalisation

And this is when a critical goal of exercise is realised:

To build our reserves to protect us from unavoidable periods of inactivity.

Because the reality is, these “disuse” events can have disastrous consequences for the health of some.

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The perils of imposed inactivity

Just as exercise can build fitness, inactivity causes the opposite.

And layer this with accelerated declines with ageing, then you’ve got a problem.

This is why even short inactivity periods are catastrophic for muscle health - particularly for vulnerable older adults.

Let’s look at a common example.

An older person who is hospitalised can:

• Spend 80% of time in bed​
• Do less than 750 steps per day​
• And lose 10% of their muscle strength after just 10 days of bed rest

This ultimately has dire consequences for physical function and independence.

It’s estimated one-third of hospitalised older adults leave hospital disabled in one or more activities of daily living they could do previously.

And that’s only the beginning.

Because these losses of course mean less daily activity, and further declines leading to more inactivity, and so on.

And so the question is, how can we best prepare for these inevitable disuse events?

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Protecting against the impact of disuse events

Unavoidable periods of inactivity are a given - but that doesn’t mean we can’t do anything to protect ourselves.

It comes down to what we do before, during, and after these events to:

• Build reserves
• Offset the declines
• And restore any losses

Let’s start with one of the most overlooked reason to exercise regularly:

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Exercise to BUILD reserves

Starting from a higher peak fitness is our best weapon against the impact of disuse events.

When muscles are “de-loaded” with inactivity, rates of muscle loss are similar regardless of starting levels.

But the impact of these losses is far greater in those with less muscle to begin with.

This means boosting your muscle mass, strength, and fitness now can help you to withstand a disuse event that may be around the corner.

Lifelong exercisers, like Masters athletes, show it’s possible to have similar muscle mass, strength, and aerobic fitness to those decades younger.

And this makes these individuals well-placed to withstand periods of inactivity.

But you don’t have to be a lifelong exerciser to protect yourself.

Even short-term increases in activity levels before planned disuse events can help.

Older adults who did a single bout of resistance exercise before 5 days of bed rest - similar to a typical hospital stay - lost less muscle in a trained leg versus the other that did no prior exercise.

The challenge of course is we often have no idea when these events will occur.

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Exercise to OFFSET losses

Maximising fitness reserves before disuse events is the ideal scenario.

But the next best thing is minimising the losses by taking action during inactivity.

Now it’s important to recognise periods of disuse can look very different.

In some instances, little-to-no physical activity is possible. But others may allow small levels of activity - which can be enough to slow the declines.

Resistance training is our best antidote to muscle loss during inactivity not due to illness or injury (such as periods of bad weather or stay-at-home orders).

In older men (aged about 70) who underwent 2 weeks of reduced activity (<1500 steps per day), very low-load resistance training (30% 1-RM) 3 times per week was enough to completely offset losses of leg muscle (fat-free) mass.

But situations where limited activity is possible, such as injury of a limb, call for more creative solutions.

One example is leveraging the “cross-education” effect - where training one limb improves performance of the opposite untrained side.

Younger individuals whose arms were placed in a cast for 4 weeks lost considerable strength (-22%) and muscle mass (-4%) - but these changes were completely offset by resistance training the opposite arm 3 times per week.

So maintaining some level of activity - even only in specific body regions - could offset the impact of disuse periods.

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Exercise to RESTORE fitness

It’s reasonable to expect some loss of fitness after a period of inactivity.

So the next goal is to restore any losses.

And in doing so, work towards re-building your reserves to withstand the next disuse event to come your way.

This is where age also has an impact.

Younger individuals can recover lost muscle mass and strength with relative ease.

But since older adults are less able to respond to anabolic stimuli (like exercise or protein intake) - known as anabolic resistance - they don’t bounce back as easily.

And a harsh reality is building muscle takes about 5 times longer than it’s lost with inactivity.

So the challenge is recovery from inactivity is slower in older adults - and may not be completely reversible.

But this aside, we should remember exercise has MANY benefits for mobility, cognitive, and metabolic health.

So even if the impact of muscle disuse can’t be fully reversed, getting back to any level of activity is better than not.

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Recipe to prepare for muscle disuse

The best way to protect yourself from unavoidable disuse events is resistance training:

• At least twice per week
• Using lower-to-higher loads
• With multiple sets per exercise
• Progressing to higher volumes or loads as strength improves

And coupled with increased general activity and reduced sedentary time, too.

Of course this is all easier said than done.

Which is why we need to spread awareness of the benefits of resistance training, address barriers to its implementation, and tackle persistent myths stopping more from taking action.

Only then can more people better prepare themselves for inevitable periods of muscle disuse.

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Exercise - for when you need it the most

Sure, exercise is about improving your fitness.

But it’s as much about preparing you for when your can’t exercise, too.

This is where regular doses of exercise - however small - are like compound interest in a savings account.

Because the benefits really do compound over time - for when you need them most.

So, will you invest today?

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As always, thanks for being here!

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Until next week,

Jackson

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Send me a quick message or email - I'll reply to every one!

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IMPORTANT:

The information contained herein is of general nature only and does not constitute personal advice. You should not act on any information without considering your personal needs, circumstances, and objectives. Any exercise program may result in injury. We recommend you obtain advice specific to your circumstances from an appropriate health professional before starting any exercise program.