Muscle, Movement & Fitness

Physical activity is often discussed as a tool for weight loss. That is far too narrow. Movement changes cardiovascular demand, muscle function, glucose use, balance, bone loading, mood, mobility and the ability to remain independent with age. Australia's Health 2026 places musculoskeletal conditions among the country's largest sources of disease burden and identifies physical inactivity as one of the modifiable risks contributing to chronic disease.[1]

Primary source: Australian Institute of Health and Welfare, Australia's health 2026.

The Australian picture

Musculoskeletal conditions accounted for 13% of Australia's disease burden in 2024, making them the third-largest disease group after cancer and mental-health/substance-use disorders.[1]

AIHW also identifies physical inactivity among the modifiable risk factors that, together with tobacco, overweight and obesity, alcohol and unhealthy diet, accounted for around 36% of total disease burden in 2024. [1]

The Australian Government's updated 2026 movement guidance reports that an estimated 46% of Australian adults and older adults do not do enough physical activity. The new framework deliberately integrates activity, sedentary behaviour and sleep across the full 24-hour day.[2]

Movement is not one thing

Different types of movement train different physiological capabilities. Walking is valuable, but it does not fully replace strength training. Strength training does not fully replace aerobic activity. Balance work is especially important as people age. Light movement across the day matters even when someone also completes a formal exercise session.

The 2026 Australian guidelines recommend that adults undertake moderate-to-vigorous activity for 30 minutes or more on most days, muscle-strengthening activity on two or more days per week, functional activities for mobility, balance and coordination on three or more days per week, and several hours of light-intensity activity daily. They also recommend limiting and regularly breaking up prolonged sedentary time.[3]

What are we actually trying to preserve?

The goal is not merely to accumulate exercise minutes. It is to preserve the physical capacities that support health and independence: muscle strength, aerobic fitness, mobility, balance, coordination and the ability to perform everyday tasks.

Muscle becomes more important with age, not less

Loss of muscle mass and strength with ageing can reduce mobility and increase vulnerability to falls and loss of independence. Healthdirect identifies resistance training as particularly important for improving muscle mass and strength, alongside aerobic activity and adequate nutrition.[4]

This is why the Physiology First view of ageing is not simply 'keep the weight down'. Preserving strength, physical capacity and enough lean tissue to function well can be just as important as body weight.

Exercise also needs to be progressive enough to create adaptation. Doing the same very light task indefinitely may maintain a habit without continuing to challenge strength or fitness. Progression should still be appropriate to the person's health, experience and injury risk.

Fitness can be measured - but context matters

Cardiorespiratory fitness is a powerful marker of physical capacity. Laboratory exercise testing can measure it directly, while many watches and fitness devices estimate metrics such as VO2 max from heart rate and movement data.

Wearable estimates can be useful for trends when the same device and conditions are used consistently, but they should not be treated as laboratory measurements or used alone to diagnose disease.

Similarly, step counts are useful for activity awareness but do not tell us whether someone is maintaining strength, challenging cardiovascular capacity, improving balance or spending long uninterrupted periods sitting.

What is worth measuring?

The most useful movement dashboard depends on the person's age, goals and health status. It may include:

• Activity volume: steps, active minutes and how often prolonged sitting is interrupted.
• Strength: a few repeatable exercises or functional tests that show whether force and capacity are improving.
• Aerobic capacity: walking tolerance, pace, exercise heart-rate response or formal fitness testing where appropriate.
• Mobility and balance: particularly in older adults, after injury or when falls are a concern.
• Body composition: waist, weight trend and lean-mass information where useful.
• Recovery: sleep, soreness, fatigue, injury symptoms and whether performance is improving or declining.
• Clinical context: blood pressure, cardiovascular symptoms, diabetes, joint disease, medications and any exercise restrictions.

More exercise is not always better

Training works through an appropriate dose of stress followed by recovery. Too little stimulus may not produce adaptation; too much too quickly can increase fatigue, pain and injury risk.

The right starting point differs enormously between a previously sedentary person, an older adult at risk of falls, someone with heart disease, and an experienced athlete. Progression is therefore individual.

For people with chronic conditions or major symptoms, exercise can still be valuable, but the program may need input from a doctor, physiotherapist or accredited exercise physiologist.

Questions worth asking

A physiology-first movement conversation can include:

• Am I only counting steps, or am I also maintaining strength, fitness, mobility and balance?
• How much of my day is spent sitting, even if I complete one exercise session?
• Is my strength or aerobic capacity actually improving over time?
• Am I losing muscle while focusing only on scale weight?
• Do pain, breathlessness, dizziness, medication or a chronic condition change how I should exercise?
• Would a physiotherapist or accredited exercise physiologist help me establish a safe baseline and progression?

When professional assessment matters

New chest pain, fainting, unexplained severe breathlessness, sudden neurological symptoms or acute injury require prompt medical assessment. People with significant cardiovascular disease, uncontrolled blood pressure, complex chronic disease, recurrent falls or major musculoskeletal limitations should seek professional guidance before substantially increasing exercise intensity.

Pain that persists or worsens with training should not simply be pushed through without understanding the cause.

The Physiology First takeaway

Movement is medicine only when the type, dose and progression fit the person. Walking, strength, aerobic challenge, mobility, balance, light daily movement and recovery each contribute something different.

The Physiology First approach is to establish a baseline, choose measures that reflect meaningful function, train the missing capacities, recover properly and then re-measure whether the body is actually adapting.

KNOW → MEASURE → UNDERSTAND → CONNECT → QUESTION → OPTIMISE → RE-MEASURE

BETTER HEALTH THROUGH BETTER FOUNDATIONS

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