Preparing physically for SAS selection
By Deepak Shukla · Historical account and source-led commentary
The British Army sets the current requirements for SAS Reserve candidates and publishes a separate set of briefing-course assessments. My experience is in preparatory Army training and endurance sport—not in completing SAS selection or certifying applicants. For general preparation, develop fitness sustainably, recover properly and seek qualified guidance before adding demanding load-carriage sessions.
Check the current tests before designing a plan
The Army Jobs SAS Reserve role listing describes mandatory briefing-course assessments such as an assurance march, swim test, aerobic work and a strength-and-conditioning assessment; it also lists separate general Army Reserve fitness measures. Do not confuse the two. Confirm any current timings, suitability requirements and course instructions directly with recruiters. A third-party training article is not the authority for a pass mark.
Aerobic base comes first
My marathon and ultramarathon history taught me the practical value of consistent, sustainable training and adequate recovery. Those lessons are transferable as general fitness principles, not as proof of readiness for military selection. Build an appropriate base at a level that suits your present ability; if you are new to exercise or returning from injury, get qualified advice rather than copying a stranger's mileage.
Hills before weight
Hill walking, lower-body strength and gradual conditioning may be useful components of a general fitness programme. Carrying extra load can add injury risk, particularly with abrupt increases. If it is appropriate for you, work through load progression with a competent coach or healthcare professional, follow official safety guidance and avoid trying to reproduce alleged selection sessions.
Feet, kit and food
From my own endurance events, I know the value of testing footwear, clothing and nutrition without making last-minute changes. That is personal race experience. I cannot infer from it why candidates succeed or fail SAS selection. If you have persistent pain, dizziness or concerning symptoms during training, stop and seek appropriate advice.
Judgement and recovery matter too
Reliable habits, adequate sleep, safe environments and recognising when to stop are important parts of long-term preparation. Do not create avoidable risk through solo night exercises, deliberate sleep deprivation, exposure drills or pushing through injury in an attempt to imitate military selection. The Army should advise on any course-specific expectations.
A note on accuracy
Entry criteria, standards and selection dates are set by the Army and change over time. Take anything current from the Army's own UK Special Forces Reserve pages; take everything below as one applicant's experience.
What is current policy, and what is my own experience?
I applied to 21 SAS and completed preparatory British Army training in 2015–2016, but did not attempt SAS selection or serve as an SAS operator. My private Georgian training was a separate experience. Military requirements belong to the Army, not to this independent personal website.
Published sources
- British Army Jobs — SAS Reserve role, entry requirements, selection and locations
Primary source for the role and the five publicly described phases; checked 15 October 2026.
- British Army — UK Special Forces Reserve overview and recruiting contact
Official route to the latest unit advice; checked 15 October 2026.
- British Army — 21 and 23 Special Air Service Reserve
Official regiment information; use the Army for current recruitment, not my historical diary.
- Soldier magazine (October 2025) — SAS Reserve recruiting feature
Dated official magazine article. Some eligibility wording differs from the Army Jobs role page; confirm with recruiting.
The Army Jobs listing and the October 2025 Soldier article use different age wording. That is a reason to ask the recruiting unit, not to pick the most convenient figure. These references are checked as of the date above, not monitored automatically.
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