Know the Mountain

What altitude actually does

Above 2,500 m the air holds progressively less oxygen in every breath. At Namche, roughly three quarters of sea level. At Everest Base Camp, about half. Your body can adapt to this, remarkably well, but adaptation takes time and happens on its own schedule. Fitness speeds nothing up. Some of the strongest people acclimatise slowest, and nobody can train for altitude at sea level.

Acclimatisation, the honest version

The body needs days, not hours, to build more red blood cells and adjust its breathing chemistry. Everything in how we pace a route follows from three rules: above 3,000 m, raise your sleeping altitude gradually, not in leaps. Walk high, sleep low: day climbs above your bed height teach the body faster than staying put. And build in rest days that are not really rest: gentle height gain, then back down to sleep. This is why our itineraries carry “extra” days. They are not padding. They are the plan.

AMS: Acute Mountain Sickness

Recognise it: headache plus one or more of nausea, poor appetite, dizziness, bad sleep, unusual fatigue. It usually arrives 6 to 12 hours after reaching a new height. Prevent it: gradual ascent above all; drink steadily; skip alcohol and sleeping tablets up high; preventive medication exists and is worth discussing with a travel-medicine doctor before you fly. Manage it: stop ascending. A rest day at the same altitude resolves most mild cases. Worsening symptoms mean descending, and descending works. Who gets it: anyone. Previous trips without trouble guarantee nothing, and youth and fitness are not protection.

HACE: when the brain swells

Recognise it: AMS that turns sinister: confusion, clumsiness, a walk like drunkenness, unusual behaviour, crushing lethargy. The stumble test is the classic sign; someone who cannot walk heel-to-toe in a straight line is in danger. Prevent it: treat AMS seriously and never ascend with symptoms. HACE is almost always AMS that was pushed. Manage it: descend immediately, even at night, even carried. Oxygen and emergency medication help; descent cures. This is a life-threatening emergency measured in hours. Who: rare below 4,000 m, and almost always preceded by warnings that were ignored.

HAPE: when the lungs fill

Recognise it: breathlessness at rest, not just on the move. A cough, sometimes wet. Crackling breath, blue lips, a chest that will not catch up. It can arrive without AMS first, often on night two or three at a new height. Prevent it: the same gradual ascent, plus honesty about respiratory infections; a chest cold at altitude deserves caution, not bravado. Manage it: descend, oxygen if available, keep the person warm and upright. Medication exists; descent remains the treatment that works. Another hours-not-days emergency. Who: the fast ascender, the person with a cold, the one who says they are fine.

The golden rules, all of them

Any illness at altitude is altitude illness until proven otherwise. Never ascend with symptoms. Never leave someone with symptoms alone. Never descend alone. Tell your guide everything, early: the person who reports a headache at lunch is easy to help; the one who hides it until dark is not. Summits are optional. Descent is always an option. And the daily oximeter checks on our journeys are not theatre: trends matter more than numbers, and the habit of honesty they build is the real safety equipment.

What the mountain actually asks

Consecutive days of 5 to 7 hours on your feet with 600 to 1,000 m of climbing, carrying 5 to 8 kg, at decreasing oxygen. Train for that, specifically. Long back-to-back hill days beat any single heroic workout. Stairs, hills and loaded walking beat the treadmill. Strong legs descend safely; most trail injuries happen going down, tired.

The 8 to 12 week shape

Weeks 1 to 4, build the habit: three walks a week, one long. Weeks 5 to 8, add weight and back-to-back days: the weekend double is the single most useful session in trekking. Weeks 9 to 12, peak with your longest days, then ease off; arrive rested, not wrecked. Already active? Convert fitness to specificity: cyclists and runners have the engine but not the descent legs or the pack shoulders.

Fit for what, exactly

Steady journeys ask for honest walking fitness and no more. Demanding adds altitude endurance: the consecutive-days test at full length. Severe means all of that plus reserve: the capacity to do the hardest day of your life at 3 am and still descend well. If a journey’s grade and your training diary disagree, believe the diary, and tell us; downgrading a plan is wisdom, not defeat.

The part nobody trains

Sleep in unfamiliar places, cold mornings, simple food, shared rooms, no shower. Comfort resilience is trainable too: camp before you commit, walk in rain on purpose. The mind quits before the legs more often than the reverse.

The layering system, once and properly

Next to skin, a wicking base, never cotton. Then insulation that fits the day: fleece or light down, doubled up high. Then the shell, real waterproofing with real venting, because you will wear it in wind more than rain. Legs follow the same logic lighter. The system’s skill is changing layers early: before the sweat, before the shiver.

The three tiers, matching our journeys

Trek kit (every Steady and Demanding journey): broken-in boots, the layer system, a −10 °C comfort sleeping bag where teahouses run cold, poles, 30 to 40 litre pack, headlamp, water treatment, sun defence for high-altitude light. Climbing kit (the 6,000ers): everything above plus double boots, crampons, harness, ice axe, jumar and abseil device, expedition mitts, a bag rated −15 °C or better. We advise renting the technical layer for first summits; conviction before investment. Expedition kit (the technical peaks and beyond): the long, specific list that deserves a conversation, not a webpage; it starts when you talk to us.

What not to buy

The second warm jacket fear wants. Cotton anything. New boots for an old trek. Gadgets whose batteries die at −10 °C. The heaviest version of everything: on a porter-supported journey your limit protects someone else’s back, and that matters more than your spare options.

Weather windows

Mountains have their own schedules. Passes and summits are attempted when the window opens, not when the itinerary says; that is why real plans carry slack and real leaders seem patient to the point of boredom. The forecast is a probability, the sky is a fact, and the mountain will still be there.

Turnaround discipline

Every summit day has a time after which up is no longer safe, decided in daylight and honoured in the dark. The mountain decides more than the calendar does; the summit is optional, the descent is not, and the strongest thing said on any mountain is “not today”.

Insurance, the unglamorous lifesaver

Standard travel policies stop below where our journeys go. What matters: cover to your journey’s maximum altitude, helicopter evacuation explicitly included, trekking or climbing named as covered activities, and for climbs, cover that says so in writing. Carry proof; in an emergency, the policy number moves faster than sympathy. We check this before every departure because the day it matters, nothing else does.

Guides, permits and the system

Most regions we travel require licensed guides and permits by law, and the law is right: the system funds trails, tracks trekkers and feeds rescue. Where rules are looser, we hold the same standard anyway. The paperwork is part of the mountain.

Walk clockwise around stupas, mani walls and chortens. Ask before photographing people; a smile and a gesture is a complete sentence. Dress modestly in villages and monasteries. The porter carrying your bag is a professional at the top of a hard trade: fair loads, fair treatment and genuine thanks are minimums, not virtues. Pack out what you pack in; above the treeline, decades pass before litter does. Buy local where you can: the teahouse dal bhat funds the trail more than any permit. And learn ten words of the local language; they are worth more than any tip.