Managing Muscle Cramps During an Ultramarathon

A muscle cramp during an ultramarathon can stop a runner as abruptly as a blocked gate. Most are brief, painful contractions in the foot, calf, hamstring or quadriceps, and many settle once the muscle is rested, stretched and loaded more gently. The right response is calm and specific, rather than pushing through the pain or automatically taking salt.

Exercise-associated muscle cramps are usually linked to neuromuscular fatigue and the demands placed on a muscle. Heat, cold, altered running mechanics and pre-existing tightness can contribute. Dehydration or electrolyte loss may worsen the situation, but they do not fully explain most cramps, so prevention based on a single fix can disappoint.

Australian runners need to prepare for sharp temperature changes, long transfers between cities and reliable access to fluids on remote routes. Whether racing near Melbourne, Sydney or Canberra, or travelling to a mountain course in Victoria or New South Wales, a sound plan protects performance and judgement when a cramp appears.

What the Muscle Is Doing

A cramp is an involuntary, sustained contraction rather than simple soreness. It may begin as a twitch, then pull the toes under, lock the calf or make a hamstring feel hard and rigid. The exact mechanism is not completely settled, which is why stretching alone cannot carry the entire prevention strategy.

Fatigued muscles often cramp during lengthened positions, downhill running or repeated contractions. A cool night can produce the same problem without obvious fluid loss. Salt-heavy sweating can create a separate concern, and a runner who drinks large volumes of plain water may risk dilutional hyponatraemia, with headache, nausea, confusion or seizures.

Location matters. A painful calf after pushing hard on a climb may be a local cramp, while whole-body symptoms, altered behaviour or a very high temperature suggest systemic illness. That distinction changes the response, so assessment should happen before trying to continue.

The First Ten Minutes

Stop in a safe place, lower your effort and move into shade or shelter if needed. If the area allows, walk gently while stretching the affected muscle. Hold a mild static stretch for about 20 to 30 seconds, breathe normally and avoid bouncing or forcing the joint through a painful range.

If you are alert, able to swallow and not already overdrinking, take controlled sips from your planned drink. A mixed drink with carbohydrate and modest sodium is often more useful than chasing a potent salt tablet. Extra water should not be forced, and concentrated electrolytes are a poor substitute for ordinary fluids for many runners.

Once the contraction releases, restart slowly with short, smooth strides and reduce the downhill or technical section that triggered it. If the cramp returns repeatedly, weakens the muscle or causes an unusual gait, do not keep running through it. Continuing can turn a manageable cramp into a fall, tendon injury or dehydration caused by impaired movement.

Training for Fewer Cramps

Training is the most durable preparation. Long runs should expose pacing errors, late-race fuel problems and muscles that stiffen after repeated hills. Practise walking while eating, drinking on a schedule and maintaining form when fatigue arrives, rather than waiting for race day to reveal these limits.

Heat acclimatisation matters for summer ultras, especially around Brisbane and inland Canberra, while Melbourne can shift quickly from a cool morning to a hot afternoon. Build tolerance through measured exposure, wear light clothing and use cooling where permitted. In Sydney, humidity can limit evaporation, so shade and a conservative pace may matter more than a large fluid target.

Strength work can improve calf and hamstring resilience, while gradual changes to footwear, terrain and downhill volume can reduce surprise. Research on pre-event stretching is mixed, so a brief warm-up and regular mobility work are sensible without being treated as a guarantee. Cramping history also deserves attention during training, especially when it repeatedly occurs at a particular pace or hill.

Fuel, Fluids and Local Products

Fuel supports more than cramps. During a long event, carbohydrate helps maintain pace, while sodium may be useful for people who lose heavily salty sweat. Australian supermarkets, pharmacies and service stations sell sports drinks, powders, gels and electrolyte tablets, but products vary widely in sugar and sodium. Reading the Australian nutrition panel is more reliable than judging by flavour or marketing claims.

Test the exact product during training because unfamiliar sweetness can cause nausea and a concentrated mix can delay stomach emptying. Plan drink volume according to the event, weather, personal sweat rate and tolerance; thirst is a useful check, not permission to drink unlimited fluid. A useful secondary reference is practical cramp guidance when putting those pieces together.

Australian rules are relevant when gels or powders cross into supplement territory. Food labels must meet Food Standards Australia New Zealand requirements, while concentrated products are best chosen through the Australian Institute of Sport’s Sports Supplement Framework, which identifies batch-tested options and reduces the risk of contaminated or prohibited ingredients.

Terrain, Pacing and Australian Conditions

A route changes cramp risk with it. A Canberra or Blue Mountains course may combine long climbs, exposed ridges and sudden descents, while a coastal Brisbane event can add humidity and a fast course. Check the race’s elevation profile, cut-offs and water spacing, then rehearse the pace you expect to hold rather than the pace that feels comfortable in the first hour.

Adjusting technique is often more valuable than adding nutrition at the first cramp. Shorten your stride on technical ground, avoid locking the knee on descents and slow sufficiently to keep the calf from overworking. When shoes become wet, change them if available; a small blister can alter your gait and trigger a cramp that looks like a muscle problem.

Local habits shape the risk before the start. Many runners use a service station to top up supplies, leave early for a trailhead because of parking restrictions, or carry more fluids than expected. Those habits are sensible when tested, but they should follow an actual drinking plan rather than anxiety about dehydration. For crews and event workers, Safe Work Australia guidance and state work health and safety laws also make heat-risk controls, shade, drinking water and illness escalation part of responsible event planning.

When Symptoms Need More Attention

Call 000 and seek urgent help when cramps occur with confusion, collapse, seizure, severe headache, repeated vomiting, loss of coordination or a dangerously high body temperature. These signs point towards heat illness, hyponatraemia or another emergency rather than an isolated cramp. Do not leave the affected person alone, and move them somewhere cool while help is arranged.

Persistent or unusually widespread cramping also deserves medical review. The same applies to weakness that does not settle, a hot swollen limb, chest pain, breathlessness at rest or dark urine after severe exertion. These are not normal race symptoms, even if the finish remains visible or event pressure makes ignoring them tempting.

After a race, replace fluid gradually, eat a balanced meal with carbohydrate, protein and sodium, and monitor how the muscles feel over the next day. A cramp that repeatedly appears at the same point in training may require assessment of gait, footwear, fuelling or health rather than another improvised electrolyte fix.

A Race-Day Response Plan

A simple race-day sequence keeps judgement available. Stop, assess the whole person, stretch gently, take a measured drink if appropriate, and resume only when the muscle feels normal and your gait is controlled. If the cramp does not resolve, shorten the race or withdraw according to the event rules and your medical needs.

Carry what supports that sequence: your planned fluids, one tested electrolyte source, a warm layer for a cold plateau, spare socks, phone and identification, plus any prescribed medication. Tell the nearest aid-station volunteer what happened, including fluid intake and the exact symptoms, rather than saying only that the calf locked.

Tomorrow, put a labelled drink bottle beside your race shoes and write the stop–assess–stretch–resume sequence on its lid; complete that setup before any further long training run.