Annapurna Base Camp Trek

What actually ends a trek

It is almost never cardiovascular fitness. People who fail to finish a multi-day trek are usually stopped by one of four things: knees that give out on descent, a pack that becomes unbearable by day three, feet that blister past the point of walking, or altitude sickness that no amount of fitness would have prevented.

That matters for how you train. A training plan built entirely around aerobic capacity — long runs, cycling, the treadmill — prepares you well for the one thing least likely to stop you, and barely at all for the other four. The strongest predictor of finishing is not your best five-kilometre time. It is whether your weakest capacity is strong enough, because a chain fails at one link.

This is why our readiness tool reports the largest single gap rather than an average score. An average flatters exactly the profile most likely to struggle: the strong runner who has never carried fifteen kilos downhill for six hours.

The five capacities, and how to train each

Sustained aerobic work is the base, and it should be genuinely easy. Most of your hours belong at a conversational pace — able to speak in full sentences. The purpose is to build the aerobic machinery that lets you walk for eight hours on consecutive days, not to make you fast. Two to three sessions a week, building toward one long day at the weekend.

Load carriage is the capacity most often skipped and most often regretted. A pack changes your gait, your balance and where fatigue lands. Start at roughly half your expected trek load and add weight before you add distance. By the final block you want at least one weekly session at full pack weight over real terrain.

Legs need to be strong single-legged, not just double-legged. Hiking is a series of single-leg loading events, and a strong back squat does not automatically transfer. Step-ups, split squats and lunges — loaded, and taken through the range a high step actually demands.

Back-to-back days are their own skill. A single hard weekend day tells you little about how you will feel on the fourth morning. Once a month, walk long on both Saturday and Sunday. That second morning is the closest simulation of a trek you can get at home, and it is where most plans quietly discover their gap.

Descent tolerance is the one people find out about too late. Going downhill loads the quadriceps eccentrically — the muscle lengthens under tension — and that is what produces the delayed soreness that turns day four into a limp. Eccentric work is also uniquely protective: the same stimulus that hurts you once makes you far more resistant next time. Train descent deliberately, not as the incidental half of an uphill session.

• Sustained aerobic — conversational pace, most of your weekly hours
• Load carriage — build weight before distance, finish at full pack
• Single-leg strength — step-ups, split squats, loaded lunges
• Consecutive days — one back-to-back weekend a month
• Descent — deliberate downhill work, not an afterthought

Altitude: what training can and cannot do

This is where honest advice matters most. Cardiovascular fitness does not protect you from acute mountain sickness. Fit young people get altitude sickness; unfit older people sometimes do not. Susceptibility varies between individuals in ways that are not well predicted by any measurement you can take at sea level, and the best predictor anyone has is your own history at altitude.

What fitness does buy you is margin. A trek that leaves you exhausted every evening gives you nothing left for the work of acclimatising, and it makes it far harder to tell ordinary tiredness from the early signs of something worth acting on. Arriving strong means the altitude is the only thing you are fighting.

The things that actually manage altitude risk are ascent profile, hydration, and a genuine willingness to descend. Those are itinerary and judgement decisions, not training ones, and we plan them with you before departure rather than leaving them to the mountain.

A sixteen-week shape

Weeks one to four build the base: easy aerobic volume, twice-weekly strength, and a pack introduced at light weight so your body learns the gait early.

Weeks five to ten add load and terrain. Pack weight climbs toward target, long days get genuinely long, and descent work becomes its own session rather than the return leg of a climb.

Weeks eleven to fourteen are the specific block: full pack, real elevation, and the back-to-back weekends that tell you the truth about your recovery.

The final two weeks come down. Volume drops sharply while intensity stays; you arrive rested rather than freshly trained. Nothing you do in the last fortnight will make you fitter for the trek, but plenty could make you more tired for it.