Start with your current pattern
Write down a normal fortnight before adding anything. Include work, study, sleep, general activity, existing running and sessions you already recover from comfortably. Without that baseline, a borrowed 'Commando preparation week' may hide an abrupt workload jump. The Royal Navy provides its own fitness advice; where it applies to you, start there.
Protect the difference between strength and endurance
Aerobic activity and strength work contribute differently. The NHS advises adults to combine aerobic activity with major-muscle strengthening at least twice weekly, while recognising that individuals have different starting points. These are broad public-health guidelines, not Royal Marines standards, and they should not be mistaken for a selection prescription.
Place supervision where it matters
Swimming technique benefits from competent instruction, and people returning after injury or a long break may need individual medical or coaching advice. A sustainable plan makes time for those conversations rather than squeezing them into an already crowded week. Water-confidence work belongs in an appropriate pool or supervised environment, not a dangerous imitation of a military test.
Adjust based on evidence
Look for what the week actually produced. Were you able to complete ordinary duties? Did soreness, fatigue or persistent pain require changes? When your ability to recover declines, repeating the same plan more fiercely is not proof of discipline. Qualified advisers can help adjust workload; no public guide can diagnose an individual.
The value of repeatability
A preparation plan should survive missed buses, family obligations and imperfect weather. An optional easier session and a sensible rest day can make the entire block more reliable. The objective is to arrive capable and healthy for authorised assessment, not impress a social-media audience with training volume.
An exercise to make this useful
Build a seven-day calendar from the commitments you cannot move. Mark where supervised swimming, strength, endurance and recovery could realistically fit. If the plan assumes every day goes perfectly, simplify it.
Use the free planning tool ↗Verify before you act
Sources and official guidance
These references support the published pathway or general safety guidance. An independent exercise is our own educational example; it does not reproduce military assessments. Check any changed requirements directly with the responsible authority.