Michael Turner
Aim for 3,500–5,500 kcal in a 24-hour period for most hikers carrying 10–20 kg on mixed trails; increase to 5,500–6,500 kcal with heavier loads, faster pace, steep elevation gain or sub-freezing conditions.
Estimate basal energy expenditure using Mifflin–St Jeor: men: BMR = 10×weight(kg) + 6.25×height(cm) − 5×age + 5; women: 10×weight + 6.25×height − 5×age − 161. Apply an activity multiplier: light walking ≈1.4–1.6, moderate loaded trekking ≈1.8–2.0, strenuous high-altitude or heavy-pack movement ≈2.2–2.6. Add 10–20% for prolonged cold, wet exposure or highly technical terrain.
Macronutrient guidelines: aim for ~55–65% of total energy from carbohydrates, 25–35% from fat and 10–15% from protein; alternatively target ~5–8 g carbohydrate and 1.2–1.6 g protein for each kilogram of body mass across a 24-hour span during sustained high-output activity. Prioritize quick-access carbs while keeping protein adequate for muscle repair.
Pack high energy-density items: nuts and nut butter (~560–650 kcal in 100 g), chocolate and energy bars (~450–600 kcal in 100 g), cured meats and hard cheese (~350–450 kcal in 100 g), pure fats (~900 kcal in 100 g). Build mixed meals around ~300–500 kcal in 100 g to balance mass and taste; favor concentrated snacks for calorie-to-weight efficiency.
Sample distribution for a 75 kg person targeting 4,500 kcal in 24 hours: breakfast 900–1,200 kcal, on-trail snacks 1,200–1,600 kcal, lunch 700–900 kcal, dinner 900–1,300 kcal. Carry an emergency buffer equal to 10–20% of planned energy to cover unexpected exertion, route changes or delays.
Calculate energy needs from body mass, hiking hours, and terrain intensity
Aim for 45–55 kcal for each kilogram of body mass across a 24‑hour period during loaded hiking on moderate trails; use the formula below to tailor intake to weight, hours on trail, and terrain difficulty.
Quick formula
Total energy (kcal) = BMR + Movement burn. BMR ≈ body_mass_kg × 22 kcal (use 20–24 kcal for individual adjustments by sex, age, fitness). Movement burn = hiking_hours × body_mass_kg × activity_rate, where activity_rate is chosen from the table: easy = 3 kcal·kg⁻¹·hr⁻¹, moderate = 5 kcal·kg⁻¹·hr⁻¹, strenuous = 7–9 kcal·kg⁻¹·hr⁻¹. Add pack load adjustment: +0.5 kcal·kg⁻¹·hr⁻¹ for each 10 kg of carried load (linear approximation). Apply environmental modifier: +5% for cool, +10–15% for cold/wet conditions.
Worked examples
Example A – 70 kg, 10 hours, moderate terrain, 12 kg pack: BMR = 70×22 = 1,540 kcal. Base activity_rate = 5; pack adj = (12/10)×0.5 = 0.6 → activity_rate = 5.6. Movement burn = 10×70×5.6 = 3,920 kcal. Total = 1,540 + 3,920 = 5,460 kcal → round to ~5,500 kcal for planning.
Example B – 60 kg, 6 hours, strenuous terrain, 15 kg pack, cold: BMR = 60×22 = 1,320 kcal. Base activity_rate = 8 (choose mid of 7–9); pack adj = (15/10)×0.5 = 0.75 → activity_rate = 8.75. Movement burn = 6×60×8.75 = 3,150 kcal. Subtotal = 4,470 kcal; add 10% cold penalty = 4,917 kcal → plan ~4,900–5,000 kcal.
Use the formula to input your own weight, planned hours, terrain level, and pack mass; round final targets to the nearest 100 kcal for meal planning and add small buffers (200–400 kcal) for unexpected exertion or long hours.
Adjust energy for load, elevation gain, and hiking pace
Add 8–12% extra energy for each additional 5 kg carried above a 10 kg base; add 5–15% for 300–1,000 m net ascent in a single stage, and 15–25% for >1,000 m; increase 10–20% when average moving speed exceeds 4 km/h on sustained non-technical trails.
Practical adjustment method
- Establish a baseline energy target (kcal) from body mass and time moving.
- Pack-weight adjustment (W): 8–12% per 5 kg above 10 kg. Equivalent: ~1.6–2.4% per 1 kg.
- Elevation adjustment (E): 5–15% for 300–1,000 m ascent; 15–25% for >1,000 m in one stage.
- Pace adjustment (P): +10–20% when average moving speed >4 km/h on sustained non-technical terrain; reduce P to 0–5% for speeds <3 km/h or frequent breaks.
- Combine multipliers: Adjusted = Baseline × (1+W) × (1+E) × (1+P). Use the lower bound of each range for conservative planning, upper bound for high effort or poor conditions.
Example and limits
- Example: Baseline 3,000 kcal. Extra 10 kg (W ≈ 16–24%), ascent 1,200 m (E ≈ 15–25%), fast pace (P ≈ 15%). Multiplicative result ≈ 3,000 × 1.20 × 1.20 × 1.15 ≈ 4,968 kcal. Summed percentage method would give ~4,650 kcal; multiplicative is safer for stacked stressors.
- Cap adjustments at +60–80% above baseline to avoid unrealistic totals; if calculated need exceeds that, reduce carried mass or split the stage.
- Small reductions matter: removing 1 kg lowers required energy by ~1.6–2.4%, so shaving 3 kg cuts need by roughly 5–7%. For lightweight ID and packing aids see best luggage tags to use.
Quick rules: add the pack-weight percentage first, then elevation, then pace; prefer multiplicative stacking; choose conservative bounds for long multi-stage trips and upper bounds for short, high-intensity stages.
Target energy by sex, age, and body-fat or fitness level
Men 18–35 with 10–18% body fat and high aerobic fitness (VO2max >50 ml·kg−1·min−1): 3,000–3,800 kcal in a 24‑hr cycle. Women 18–35 with 18–25% body fat and high aerobic fitness: 2,400–3,000 kcal in a 24‑hr cycle.
Ages 36–50: subtract about 150–250 kcal from the 18–35 baseline for the same sex and fitness category. Ages 51–70: subtract about 300–450 kcal from the 18–35 baseline. Larger lean-mass individuals require higher values than these adjustments suggest.
Fitness modifiers: low aerobic fitness or minimal training – multiply resting metabolic rate by ~1.6–1.8; moderate training and steady hiking pace – ~1.9–2.1; high fitness and sustained fast pace or long hours – ~2.2–2.6. Apply the chosen multiplier to estimated resting metabolic rate to get target kcal for a 24‑hr cycle.
Body-fat modifiers: each 5% lower body-fat below typical ranges increases energy needs by roughly 50–120 kcal in a 24‑hr cycle (higher lean-mass and energy turnover); each 5% higher body-fat above typical ranges reduces needs by roughly 40–90 kcal in a 24‑hr cycle. Use these adjustments on top of the fitness multiplier.
Quick example: Mifflin–St Jeor BMR ≈1,700 kcal for a 75 kg, 30 y male; with moderate training multiplier 2.0 → target ≈3,400 kcal in a 24‑hr cycle. If body fat is 12% (leaner), add ~100 kcal → use ≈3,500 kcal; if body fat is 25% (higher), subtract ~80 kcal → use ≈3,320 kcal.
Choose high‑energy‑density foods and convert kcal to weight
Aim for food items that deliver 130–160 kcal/oz as a baseline; choose ≥180 kcal/oz for cold or very strenuous outings.
Food energy-density table
| Item | kcal/100 g | kcal/oz | g for 1,000 kcal |
|---|---|---|---|
| Olive oil | 884 | 250.7 | 113.1 |
| Peanut butter | 588 | 166.8 | 170.1 |
| Almonds | 579 | 164.3 | 172.7 |
| Trail mix (nuts + dried fruit) | 550 | 156.0 | 181.8 |
| Dark chocolate | 546 | 154.9 | 183.2 |
| Granola | 471 | 133.6 | 212.3 |
| Cheddar | 403 | 114.3 | 248.1 |
| Beef jerky | 410 | 116.2 | 243.9 |
| Dehydrated meal (reconstituted density) | 375 | 106.3 | 266.7 |
| Tortilla | 330 | 93.6 | 303.0 |
Quick conversion method and examples
Formula: weight (g) = energy_target_kcal × 100 / (kcal/100 g). Example A: for 3,000 kcal using peanut butter (588 kcal/100 g) → 3,000 × 100 / 588 = 510 g. Example B: same 3,000 kcal supplied by olive oil (884 kcal/100 g) → 3,000 × 100 / 884 = 339 g. Swapping lower-density items for oil or nut butter cuts pack weight substantially.
Packing strategy: favor concentrated fats (oils, nut butters, commercial fat bars), mix a few high-density snacks with lighter staples, portion into single-use packets to avoid extra packaging, and calculate grams for your total kcal target before final packing so you can compare weight trade-offs precisely.
Plan resupply strategy and kcal targets for multi‑night routes
Recommendation: carry the number of full meals needed for the segment plus a 20% energy buffer; for stretches longer than four nights add an extra 2–3 meals and arrange a maildrop or town pickup.
Use an energy‑density baseline of ~160 kcal/oz for mixed high‑energy foods (nuts, bars, fatty snacks). That equals about 2,560 kcal/lb (≈5,640 kcal/kg). Example conversions: 3,800 kcal in a 24‑hour period weighs ≈21.9 oz (~620 g); a 7‑night supply at that rate totals ≈10.4 lb (~4.7 kg), illustrating why staged resupply is usually lighter than carrying all food at once.
Resupply spacing rules of thumb: plan town or drop points every 2–5 nights where possible. For maildrops, send packages 5–7 calendar days ahead of your projected arrival to allow postal delays; place food inside vacuum bags, then inside a labeled hard plastic container or resealable bag; include name, arrival date window and a reliable contact phone number.
Pack organization: pre‑portion meals into numbered pouches for each camp night and daytime snacks for each hiking segment; weigh and record each pouch in a spreadsheet or route plan. If a segment is long and remote, split the load: carry the first half of the food, deposit a secure cache with proper permissions or rely on a scheduled maildrop for the second half.
Contingency planning: keep a waterproof emergency stash of 1,000–1,500 kcal (high‑fat bars or nut butter sachets) accessible on the outside of your pack. If a resupply is delayed, reduce intake to 70–80% of planned energy until you reach the next point and avoid rationing that drops below those levels for more than 24–48 hours.
Tradeoff example for decisions: a 10‑night route with resupply at night 5 requires carrying ~5 nights worth of food. At 3,500 kcal in a 24‑hour period and 160 kcal/oz that equals ~21.9 oz × 5 = 109.5 oz (~6.8 lb / ~3.1 kg). If maildrop is available at night 5 you cut that carried weight roughly in half.
Equipment tip: use compact, crush‑resistant containers for maildrops and secure labeling; for recommendations on robust luggage and cases consult best luggage companies in the world.
Monitor signs of under-fueling and steps to recover energy on the trail
Stop moving, sit, and ingest 200–350 kcal (use easy sugars) plus 10–20 g protein; drink 300–500 ml electrolyte fluid and rest 15–30 minutes – if symptoms improve, resume at a slower pace and eat a solid snack within the next hour.
Objective signs that intake is insufficient: sustained pace drop >20% compared with expected speed; resting heart rate elevated by more than 8–12 bpm above your normal baseline; repeated shortness of breath with minimal effort; urine darker than pale straw (amber or brown); muscle cramps or tremor; lightheadedness, blurred thinking, or slurred speech; new nausea or vomiting. Measured hypoglycemia (glucometer <70 mg/dL) requires immediate fast sugar intake.
Immediate recovery sequence: 1) fast sugars: glucose gel (~100 kcal each), 3–4 glucose tablets, soda or honey (aim for ~20–40 g simple carbs immediately); 2) add protein/fat within 15–30 minutes (nut butter packet, cheese, jerky) to stabilize levels; 3) sip electrolyte solution 300–500 ml during the first 30 minutes and continue 500–1,000 ml over the next 2–4 hours; 4) rest seated until heart rate and cognition return near baseline (usually 15–30 minutes). If no improvement, stop moving and set a camp or call for evacuation.
Field food examples with approximate energy: single energy gel ≈100 kcal, granola bar 200–300 kcal, 2 tbsp nut butter ≈200 kcal, 1 cup trail mix 400–500 kcal, 2 oz hard cheese ≈200 kcal, 2 oz beef jerky ≈150 kcal. Combine a sugar source plus a protein/fat item after initial recovery to prevent rebound drops.
Preventive adjustments after an episode: add an extra 300–800 kcal spread over the next 4 hours; schedule compact snacks every 45–60 minutes while moving (nuts, energy bars, dried fruit); lighten pack load if episodes repeat; if episodes persist for multiple outings, increase baseline intake by about 15–25% and consult a clinician or sports nutritionist.
Red flags needing urgent descent or medical care: loss of consciousness, severe confusion, persistent vomiting, chest pain, measured glucose <54 mg/dL that does not correct after repeated treatment, or symptoms that worsen despite eating and resting.
Gear-care aside: clean dried mud and sweat from footwear and fabric promptly to prevent material damage – see best pressure washer for pool deck for a strong cleaning option before long-term storage.
FAQ:
How many calories per day should I eat on a multi-day backpacking trip?
Daily needs vary a lot with pace, pack weight, terrain and weather, but a practical range for most people on a multi-day trek is about 2,500–5,000 kcal per day. Light days with short mileage and a light pack often land near 2,500–3,000 kcal. When you hike long hours with a heavy pack, expect 4,000 kcal or more. A simple rule of thumb: add 300–600 kcal for each hour of sustained hiking, depending on speed and load. Choose compact, high‑calorie foods (nuts, nut butters, dense bars, dehydrated meals with added oil) and eat frequently during the day. Monitor how you feel and your body weight across the trip and increase intake if you feel unusually tired, cold, or are losing significant weight week to week.
How can I calculate my specific daily calorie needs for an extended backpacking trip?
To get a personalized estimate, follow three steps. First, calculate your resting metabolic rate with the Mifflin–St Jeor formula: for men = 10×weight(kg) + 6.25×height(cm) − 5×age + 5; for women = 10×weight(kg) + 6.25×height(cm) − 5×age − 161. Second, estimate the energy spent while hiking. A practical estimate is 300–600 kcal per hour of hiking: lower end for easy terrain and light pack, higher end for steep trails and heavy loads. Multiply that hourly figure by the expected daily hiking hours. Third, add the hiking energy to your daily resting figure. Example: a 70 kg, 30‑year‑old person (male) with BMR ≈ 1,680 kcal who plans 8 hours of hiking burning about 420 kcal/hour would get ~1,680 + (420×8) = ≈5,040 kcal/day. Adjust the hourly burn up or down based on pack weight, pace and altitude. For macronutrients aim for roughly 1.2–1.8 g protein per kg bodyweight daily to protect muscle, prioritize carbohydrates for sustained energy during long days, and use fats for concentrated calories and satiety. Pack calorie‑dense items so you can meet targets without carrying excessive weight, and track weight and energy levels during the trip to fine‑tune intake on later days.
