By hour 8 of an ultra, the athlete's decision-making is impaired. The crew's job is to remove choices, not present them. This guide covers the written crew brief template, pre-prepared aid bag contents, the 3-minute aid station drill, drop-bag essentials, and the most common crewing mistakes.

This guide is part of our Ultra-Trail Snowdonia fuelling master series — read the master guide first for the full UTS protocol, then come back here for the deep dive on this single piece.

Key points

  • Aid station ETAs, expected pace per segment, what to hand over at each stop, dietary preferences, drop-bag locations, and a contingency plan for when the athlete is behind schedule.
  • Pre-mixed bottles of MIX+, a pouch of gels and bars matched to the next segment, an SLT+ sachet, dry socks if it's wet, a head torch if it's getting dark, and any specific foods you've trained on.
  • 3 minutes is the target for routine stops.
  • Asking the athlete questions instead of giving instructions, presenting options instead of handing over a pre-decided plan, not having gear pre-prepared (causing 5-minute scrambles), and not knowing the cut-off times for the athlete's race.
  • Bottles of MIX+ pre-mixed, 4 to 6 gels, 2 to 3 bars, 2 SLT+ sachets, a small first-aid kit, blister tape, dry socks, and a backup head torch with spare batteries.

Why crewing matters for ultras

An ultra is won (or lost) at aid stations as much as on the trail. A well-crewed athlete moves through aid in 3 minutes, refuelled and re-equipped, and gets back to running. A poorly-crewed athlete loses 10 to 15 minutes per stop, multiplied across 6 to 12 stops in a long race - that's an hour or more of avoidable stationary time.

Worse, by hour 8 the athlete's decision-making is impaired. Cortisol is elevated, glycogen is low, sleep deprivation is creeping in. Asking 'what do you want?' at hour 10 gets a worse answer than at hour 1. The crew's job is to remove choices, not present them.

The crew brief: what to write down

Every ultra crew should arrive on race day with a written brief covering:

  • Aid station ETAs based on the athlete's expected pace per segment.
  • What to hand over at each stop: which pre-prepared bag to bring, what's in it, what to swap from the athlete's pack.
  • Dietary preferences: what the athlete eats (and what they hate) by hour of the race.
  • Drop-bag locations: which aid stations are crew-accessible vs self-supported.
  • Cut-off times: race cut-offs and personal time goals per checkpoint.
  • Contingency plan: what to do if the athlete is 30+ minutes behind schedule, has a kit problem, or shows signs of trouble.

Print two copies. The crew chief carries one; back-up crew has the other.

Pre-prepared aid bags

One labelled bag per aid station, prepared the night before. Standard contents:

  • 2 pre-mixed bottles of MIX+ (one for each soft flask).
  • 4 to 6 gels matched to the next segment's duration (1 per 30 to 45 minutes).
  • 2 to 3 BAR50 bars for chew variety.
  • 1 to 2 SLT+ sachets for sodium top-up.
  • Real food option: a sandwich, salted potatoes wrapped in foil, or a wrap.
  • Kit essentials: dry socks if wet, head torch + spare batteries if night is approaching, gloves and a hat if temperature dropping.

Label each bag clearly with the aid station name. Use bright tape and big sharpie - crews are tired too.

Crew preparing pre-mixed STYRKR MIX+ bottles for an aid station handover

The 3-minute aid station drill

A repeatable drill that gets the athlete in and out fast:

  1. 0:00 — Athlete drops pack. Crew chief takes pack, crew #2 hands a chair (if seated) and a bottle of fluid.
  2. 0:30 — Crew swaps full bottles into pack, removes empty wrappers, restocks gels and bars in their assigned pockets.
  3. 1:00 — Athlete eats real food (potatoes, sandwich, broth). Crew chief restates the next segment plan.
  4. 2:00 — Final fluid sip, dry-sock change if needed. Crew checks athlete's vest is closed properly.
  5. 3:00 — Athlete leaves. Crew packs up.

Time it on a watch. Aid stations expand to fill available time - a hard 3-minute timer prevents the slow drift that loses races.

What to do (and not do) at aid stations

Do:

  • Greet the athlete by name and tell them where they are in the race.
  • Hand over decisions ('Eat this. Drink this.') rather than offering options.
  • Watch for danger signs: confusion, slurred speech, pale skin, refusal to eat or drink.
  • Have the next segment plan written on a card you can hand over.

Don't:

  • Ask 'how do you feel?' - the answer mid-ultra is always 'bad' and doesn't help.
  • Ask 'what do you want?' - decision fatigue compounds the problem.
  • Bring up race position or competitor splits unless asked.
  • Let the athlete sit for more than 5 minutes unless seated stops are explicitly planned.

Drop-bag essentials for self-supported sections

Some ultras have aid stations the crew can't reach. The athlete's drop bag at those stations needs to cover everything the crew would have done:

  • 2 pre-mixed bottles of MIX+ in the bag.
  • 4 to 6 gels for the next segment.
  • 1 to 2 SLT+ sachets plus a spare in case sodium losses are higher than planned.
  • Real food: a wrap, a sandwich in a sealed container, salted potatoes if the bag is delivered cold.
  • Backup gear: head torch with fresh batteries, gloves, a buff, dry socks.
  • Small first-aid: blister tape, paracetamol, anti-chafe.

Pack for the worst case. A self-supported section in bad weather with a slow-moving athlete needs more contingency than a crew-supported section in good conditions.

Final word

Great crewing isn't about emotional support — it's about removing every decision from the athlete and executing a pre-agreed plan with discipline. The brief, the bags and the 3-minute drill are the system. Trust them more than the athlete's mid-race judgement.

This guide pairs with our Ultra-Trail Snowdonia fuelling master guide — crewing is one piece of the broader UTS race-day system, alongside in-race fuelling, sodium loading and real-food strategy.

Related deep dives in this UTS series

Read the master overview at How to Fuel for UTS Snowdonia: An Ultra Trail Guide.