17/07/2025
Sun Sense.
We all recognise we choose to subject our bodies to tremendous stresses and strains through life, never more so than when temperatures hit the highs of the summer months and being able to recognise the signs high heat conditions enables us to make wise choices, mitigate risks and plan for issues so, here’s a quick summary of the illnesses which we may develop in ourselves, see in our friends or even see in others while out on the hill or mountainside. Certainly no one is saying don’t go! but going with knowledge is our best way of getting to our destination and returning, allowing us to have great experiences while enjoying the day or Expedition. Handy tips, hints and ramblings are included at the end.
Heat stress, occurs when the body's internal temperature rises due to an inability to dissipate heat, leading to potential heat-related illnesses. It's a serious concern in various settings, especially in the mountains, and can result in everything from mild conditions like heat rash to severe, life-threatening heat stroke.
Understanding Heat Stress:
Body's Thermoregulation: The body regulates its temperature through various mechanisms, including sweating and blood circulation. When our bodies mechanisms are overwhelmed, heat stress develops.
Causes: High air temperature, humidity, physical activity, and certain types of medication or clothing can contribute to heat stress.
Factors Influencing Heat Stress:
Environmental Factors: High ambient temperatures, humidity, and radiant heat sources.
Metabolic Heat: Heat produced by the body during physical activity.
Individual Factors: Age, pre-existing health conditions, and acclimatization to heat.
Clothing: Materials and colours can restrict heat loss as can the fit of clothing to the body.
Medication: Certain medications may hamper our body’s ability to regulate our temperature
Health Impacts:
• Mild Symptoms:
Heat rash, heat cramps, and heat exhaustion (characterized by fatigue, dizziness, nausea).
• Severe Symptoms:
Heat stroke, a medical emergency with symptoms like high body temperature, hot dry skin, confusion, and potential loss of consciousness.
Prevention and Management:
• Hydration: Drink plenty of fluids, especially water, to replace lost sweat.
• Acclimatization: Gradually increasing exposure to heat can help the body adapt.
• Rest and Shade: Take breaks in cool, shaded areas to allow the body to recover.
• Use Water: Using mountain streams, lochs and burns to regulate our body temperature can help, rapid immersion can cause shock and the shunting of heat to the bodies core causing further heat complication.
• Appropriate Clothing: Wear light coloured, loose-fitting clothing that allows for airflow.
• Exertion Practices: Schedule strenuous activities for cooler parts of the day and implement regular breaks, agree key places for stops or stops per hour or half hour.
• Education and Training: Mountaineers, climbers and walkers should be aware of the risks of heat stress and how to prevent it.
• First Aid: Recognize the symptoms of heat-related illnesses and seek immediate medical attention when necessary. Asking for help is a strength and not a weakness.
Heat Stress in the Mountains:
• Professionals and other groups: Ask others you are passing, about the conditions if they are coming from a known environment.
• Risk Assessment: Everyone should openly assess the risk of heat stress in their environments and implement appropriate control measures.
• Monitoring: Regularly monitor ourselves and others for signs and symptoms of heat stress.
Heat rash, also known as prickly heat or miliaria, is a skin condition that occurs when sweat ducts become blocked and inflamed, trapping sweat beneath the skin. This blockage leads to the appearance of small, red, itchy bumps or blisters, often accompanied by a stinging or prickling sensation. Heat rash is common in hot and humid conditions, especially during summer, and can affect people of all ages, including babies.
Causes:
• Excessive sweating:
Heat rash is caused by excessive sweating, which can overwhelm the sweat ducts and lead to blockage.
• Blocked sweat ducts:
Sweat ducts can become blocked due to a variety of factors, including dead skin cells, bacteria, and even certain clothing.
• Hot and humid conditions:
Warm, humid weather can exacerbate sweating and increase the likelihood of sweat duct blockage, making heat rash more prevalent.
Symptoms:
• Small, red bumps or blisters on the skin.
• An itchy or prickling sensation.
• Redness and mild swelling of the affected area.
• In darker skin tones, the rash may appear as slightly darker spots or bumps, or even white globules under the skin with darker halos.
Treatment:
• Cooling the skin: The primary treatment for heat rash is to cool the affected area and reduce sweating.
• Avoiding heat and humidity: Minimize exposure to hot and humid environments.
• Loose clothing: Wear loose-fitting, breathable clothing to allow for better airflow.
• Cool baths or showers: Lukewarm baths or showers can help soothe the skin and reduce itching.
• Topical treatments: Calamine lotion or corticosteroid creams (like 1% hydrocortisone) can help relieve itching and inflammation if safe.
• Avoidance of irritants: Avoid using perfumed soaps, lotions, or creams that may further irritate the skin.
When to seek medical advice:
• If the rash is severe or doesn't improve with home treatment.
• If signs of infection appear, such as increased pain, redness, or pus.
• If you are concerned about any symptoms or potential complications.
Heat cramps are painful muscle spasms, often in the legs, arms, or abdomen, which occur during or after physical activity in hot weather. They are a mild form of heat illness, usually caused by excessive sweating and loss of electrolytes and fluids.
Causes:
• Heavy sweating: During exercise or work in the heat, the body loses fluids and electrolytes (like sodium and potassium) through sweat.
• Inadequate fluid and electrolyte replacement: If these losses aren't adequately replaced, it can lead to an imbalance that causes muscles to cramp.
• Strenuous physical activity: Vigorous exercise in hot weather is a common trigger for heat cramps.
Symptoms:
• Painful muscle cramps: These can be sharp and sudden, often in the legs, arms, or abdomen.
• Heavy sweating: This is a sign that your body is trying to cool itself down.
• Normal or slightly elevated body temperature: Unlike heat exhaustion or heatstroke, heat cramps typically do not involve a high fever.
• Fatigue and weakness: These can also be present, as your body is under stress.
First Aid and Treatment:
• Rest and cool down:
Move to a cooler location, like an air-conditioned area, and rest.
• Drink fluids:
Replace lost fluids and electrolytes by drinking water or a sports drink like Gatorade or Powerade.
• Stretch and massage:
Gently stretch and massage the affected muscles to help relieve the cramps.
• Avoid strenuous activity:
Refrain from intense physical activity for a few hours after the cramps subside.
When to Seek Medical Attention:
• If cramps are severe, prolonged, or don't improve with first aid measures.
• If you experience other symptoms of heat exhaustion or heatstroke, such as dizziness, nausea, vomiting, or confusion.
Prevention:
• Stay hydrated: Drink plenty of fluids, especially before, during, and after exercise or work in the heat.
• Replace electrolytes: Consider sports drinks or electrolyte tablets to replenish lost minerals.
• Take breaks in the shade: If you are working or exercising in the heat, take frequent breaks in a cool, shaded area.
• Acclimatize to the heat: Gradually increase your exposure to heat to allow your body to adjust.
Heat exhaustion is a condition caused by the body overheating, often due to prolonged exposure to elevated temperatures or strenuous physical activity. It occurs when the body loses too much fluid and salt through sweating and can lead to heatstroke if not treated promptly.
Symptoms of Heat Exhaustion:
• Tiredness and weakness: Feeling unusually fatigued or weak.
• Headache: A throbbing or persistent headache.
• Dizziness and confusion: Feeling lightheaded, unsteady, or disoriented.
• Nausea and vomiting: Feeling sick to your stomach or vomiting throwing up.
• Excessive sweating: Heavy sweating, even when not physically active.
• Pale or clammy skin: Skin may appear pale, cool, and clammy.
• Muscle cramps: Painful cramps in the legs, arms, or abdomen.
• Rapid heartbeat: A noticeably faster and stronger pulse.
• Intense thirst: A strong urge to drink fluids.
What to do:
1. Move to a cooler place: Get out of the sun and into a shaded or air-conditioned area.
2. Loosen clothing: Remove any tight or heavy clothing to help the body cool down.
3. Hydrate: Drink plenty of cool water or a sports drink containing electrolytes.
4. Cool the body: Use cool water to sponge or spray the skin and fan the person.
5. Rest: Encourage the person to lie down and elevate their legs.
6. Monitor: Watch for signs of improvement. If symptoms worsen or don't improve after 30 minutes of rest and cooling, seek medical attention.
When to seek medical help:
• If symptoms worsen or don't improve after 30 minutes of rest and cooling.
• If the person experiences confusion, seizures, or loss of consciousness.
• If the person is unable to drink fluids.
• If the person has a very high temperature (40°C or above).
• If the person has difficulty breathing or is becoming unresponsive.
Heatstroke is a serious medical condition where the body can no longer regulate its temperature, and the body temperature becomes dangerously high, often above 40°C (104°F). It is a medical emergency and requires immediate treatment. Symptoms include hot, flushed skin (sometimes dry), headache, dizziness, confusion, and a rapid pulse. If heatstroke is suspected, call for emergency help immediately and begin cooling the person down while waiting for assistance.
Symptoms of Heatstroke:
• High body temperature: Usually above 40°C (104°F).
• Hot, flushed, and dry skin: May be hard to see on darker skin tones.
• Confusion and disorientation: May not know where they are or what is happening.
• Rapid, strong pulse: Heart may be beating very fast.
• Headache and dizziness: Can be severe.
• Rapid, shallow breathing: May be struggling to breathe.
• Loss of consciousness: In severe cases.
• Seizures or fits: In severe cases.
What to do if someone has heatstroke:
1. Call for emergency help immediately: Dial 999 in the UK and explain the condition is suspected heat stroke.
2. Move the person to a cool place: Get them out of the sun and into a shaded area, if this isn’t possible then make shade without moving the injured person.
3. Remove excess clothing: Help them cool down by taking off unnecessary layers of clothing or equipment.
4. Cool their skin: Use cool, damp cloths or a sheet to cool their skin. You can also fan them or use a spray bottle to mist them with cool water however tepid water is better than no water, any fluid can be used however avoid oil-based fluids.
5. Apply cooling packs: Place cooling packs if available (wrapped in a cloth) on their armpits and groin.
6. Continue cooling efforts: Keep monitoring their temperature and continue cooling them until help arrives. Don’t stop just because the casualty says they feel better.
7. Stay with them: Do not leave them unattended until professional medical help arrives and you are able to hand over the treatment to the emergency services. Be prepared to explain the 5 w’s when, where, what the history was, what happened and what you have done so far with AMPLE Allergies. Medication, past medical history, last ate or drank, the environmental issues.
Important considerations:
• Heatstroke is more serious than heat exhaustion and requires immediate medical attention.
• Older adults, young children, and people with chronic illnesses are at higher risk.
• Certain medications can make it harder for the body to regulate temperature.
• Do not give someone with heatstroke anything to drink unless they are fully conscious and able to swallow safely, small sips will avoid vomiting and wetting the persons lips can make the person feel more comfortable.
• Heatstroke can cause organ damage and be life-threatening if not treated promptly.
Sun glare, Shades aren’t just for looking cool in the mountains sun glare can be a nuisance and even a health risk, causing temporary discomfort and potentially long-term eye damage. It's important to protect your eyes from the sun's glare by using sunglasses with UV protection, wearing a wide-brimmed hat, and spending time in the shade.
Why is sun glare harmful?
UV Radiation: The sun emits ultraviolet (UV) radiation, which can damage the cornea, lens, and retina of the eye.
Photokeratitis: Excessive UV exposure can cause photokeratitis, a painful condition like sunburn of the eye.
Glare Sensitivity: Glare can cause discomfort, blurriness, and difficulty focusing, especially for those with certain eye conditions.
Long-term Effects: Prolonged exposure to UV radiation can increase the risk of cataracts and other eye diseases.
How to protect your eyes:
Sunglasses: Wear sunglasses that block 100% of UVA and UVB rays.
Wide-Brimmed Hats: Hats provide additional shade and protection for your eyes and face, so a peaked cap or wide brim is great.
Seek Shade: When possible, spend time in shaded areas, especially during peak sunlight hours.
Polarized Lenses: Consider polarized lenses for driving and activities near water or snow, as they reduce glare from reflective surfaces.
Blue Blocking Lenses: These lenses can help reduce glare and improve visual clarity, especially for those with macular degeneration.
When to seek professional help:
If you experience persistent eye pain, blurred vision, or sensitivity to light, consult an eye doctor.
If you have an underlying eye condition, it's even more important to protect your eyes from glare and UV radiation.
Sunburn is skin damage caused by overexposure to ultraviolet (UV) radiation from the sun. It typically appears as red, painful, and hot skin, which may also peel or flake after a few days. While often mild and temporary, sunburn can increase the risk of skin cancer and other health problems later in life.
Symptoms:
Redness and pain: The affected skin will be red, hot to the touch, and painful.
Tenderness and soreness: The sunburned area may feel tender or sore.
Peeling and flaking: After a few days, the skin may start to peel or flake.
In severe cases: Blisters, swelling, nausea, fever, and chills can occur.
Causes:
Excessive exposure to UV radiation from the sun and Use of tanning beds.
Treatment:
Cool compresses: Applying cool (not cold) compresses or taking a cool bath can help soothe the skin.
Moisturizers: Use a light, fragrance-free moisturizer, preferably one containing aloe vera or soy, to help keep the skin hydrated.
Pain relievers: Over-the-counter pain relievers like ibuprofen or paracetamol can help reduce pain and inflammation if safe to take.
Stay out of the sun: Avoid further sun exposure until the sunburn has healed.
Seek medical attention: For severe sunburns with large blisters, signs of infection, or if you feel unwell, seek medical help.
Prevention:
Sunblock: Factor 50 or total sunblock isn’t considered unusual due to now recognising the heath issues from exposure to the sun.
Sunscreen: Use a broad-spectrum sunscreen with an SPF of 30 or higher, and reapply it every two hours, or more often if swimming or sweating.
Protective clothing: Wear protective clothing, such as long sleeves and hats, when spending time outdoors.
Seek shade: Limit sun exposure, especially during peak hours (10 am to 4 pm), and seek shade when possible.
Warm Water Immersion Foot (WWIF), also known as "Paddy Foot" or "Jungle Foot," is a condition that occurs when our feet are exposed to prolonged periods of warm, damp, wet conditions, typically between 15-32°C (59-90°F). This can lead to skin maceration (softening and breaking down), pain, swelling, and increased susceptibility to infections. It's a type of non-freezing cold injury, like trench foot but occurring in warmer, wet conditions.
Here's a more detailed explanation:
What it is:
Warm water immersion foot is a skin condition caused by prolonged exposure to warm, wet conditions.
It's a form of non-freezing cold injury, meaning it doesn't involve freezing of the tissues, but rather damage from prolonged exposure to wet and warm environments.
Symptoms include Pain, swelling, blisters, open sores, and maceration of the skin.
The skin on the soles of the feet may appear white, wrinkled, and softened.
The condition can be painful, especially when the skin breaks down and blisters open.
Causes:
• Prolonged exposure to warm, wet conditions is the primary cause.
• Military personnel, walkers, and mountaineers, and those working in wet environments are at higher risk.
Prevention:
• Keep feet dry and clean.
• Change socks and shoes frequently, especially when wet.
• Avoid prolonged exposure to wet conditions.
• Use waterproof breathable footwear and socks when possible.
• Dry feet thoroughly, especially between toes, after exposure to water.
Treatment:
Dry and elevate the feet.
Use foot powder to reduce moisture around feet.
Rest the affected foot.
Over-the-counter pain relievers may help with discomfort and swelling.
Keep the area clean and protected from further injury.
Seek medical attention if symptoms worsen or if infection develops.
Warm water immersion foot is a preventable condition that can be managed with proper hygiene and preventative measures.
Hints, Tips and Ramblings…
Only individuals can make the right choices to ensure we don’t become a casualty from heat, and flexing our plans may include (but doesn’t have too) some of the below: -
Ensuring, we consume the correct diet and fluid intake in the days and hours before an activity helps us achieve a more enjoyable day.
Avoiding diuretics and stimulants, such as tea and coffee as these take more bodily fluids to process and can mask our body’s ability to feel and adjust to the signs and symptoms of heat. Perhaps consider switching to decaf?
Preloading our bodies, with fluids immediately before strenuous activity can help our bodies retain fluids for longer.
Warming up, regulating our pace, and cooling down all help our bodies adjust to the external temperature and helps our bodies to manage our fluid levels.
Pre-dawn starts, aren’t just reserved for winter, starting at 2 or even 3 am allows us the benefit of the cooler night and dawn air.
Siesta season, avoiding the hottest part of the day (between 11 AM and 4 PM) or the more intense period (between 12 AM and 3 PM) by resting and finding shade may make days enjoyable.
Acclimatization, to the conditions suspected on the day gives our bodies time to adjust to the surrounding weather, temperature, and humidity conditions.
Flexibility and objective, our objective is always to get back home safely, the summit is a flexible part of that plan that may, need to move to suit us, our abilities and the weather or environment on the day. There's always somewhere to go, woods, lower elevations, mountain aspects in the shade for longer periods or ridges able to catch breezes. Consider reversing the routes to have the sun on our back or being in the shade for longer. Having this flexibility rather than a ridged plan means we are more likely to have a great day.
Preparing our bodies and minds, a little TLC for our bodies with correct personal hygiene and making sufficiently robust plans including alternatives and escape routes allows for a more enjoyable mountain day.
Learn from our own mistakes, hot and cold debriefs help us become better, learn and grow so our day adds to our experience, sitting in the car or by the tent and asking what went well, what didn’t go so well and what we would change allows us to grow and become better individuals and team players.
Adopting the plod, the alpine slow-paced plod is the slow and steady rhythmic cadence which is slow enough to not need stops but fast enough to cover distance and often works well in hot conditions. Not all of us are mountain athletes and there are no prizes for speed so, try adopting a pace that we are moving at all day and comfortable to us.
Key places, discuss and decide on key places on the route where decisions can be agreed and executed.
Drinking water, how much fluid to consume is different for everyone due to our own differences as people, the quantity should be sufficient to keep our bodies heathy and sweat proficiently. In hot weather it may not be possible to carry all the fluids we need so consider collecting water on route. Sadly, much of the advice about safe to drink straight from mountain streams is incorrect due to unknown water contamination so, consider effective water treatments of filtration, chemical, UV or boiling. No process will treat all water contamination so best to double up treatments. This means we only need to carry sufficient fluids to get to the next watering hole saving weight and increasing our performance.
Our Gut, we have a primeval alarm sense often called a “gut feeling” so if something does not feel right, listen to our gut feeling as its normally right, we have had this ability for about two million years and far longer than human language.
Brut, splash it on, soaking shirts and trousers in mountain water sources and putting back on helps cool out bodies and aids evaporation. Immersing wrists or ankles in cool water has a quick effect, however, try and allow sufficient time to cool our core. Sudden cooling shunts heat to our core which can impact our organs and be dangerous often called cold water shock.
Energy consumption, In hot weather some of our systems slow down and we are not as hungry while some speed up to cope with the additional demands on our body, so we still need sufficient food to convert to energy, eating little and often helps. There foods should contain sufficient electrolytes in our normal diet to cope however, changing to light more easily consumed foods helps, nuts and raisins and other foods that give a slow energy release are often better than short energy burst foods. Worth thinking how foods travel and not all foods are suitable for being stored in a warm rucksack. The best food is that we have consumed so if bringing food off the hill we have wasted energy and may be worth switching to something different next time.
Go small, Consider decanting sun creams and insect repellents into smaller containers ensuring they are clearly marked allows us to carry less and be more efficient. It’s also worth while considering packaging food into more suitable containers such as zip lock bags or pouches. Anyone that’s carried crisps on the hill soon realises these turn into crumbs.
Having the moral strength, to turn back deserves far more resilience than to push on regardless, our history is full of dead mountaineers that did not make the right decision and paid dearly for that error in judgement. Planning our day having alternatives and escape routes is all part of the adventure however, a successful day is making it home safely, being self-reliant and not needing intervention from others. Mountaineers and walkers who can make sound judgement calls are far more intelligent than supper fit individuals that rely on strength to get them out of situations they have put themselves in.
Consumption, knowing how much fluid we are drinking allows us to monitor and control our fluid intake, drinking little water often helps our bodies process fluid in hot weather however, if using a water bladder consider topping this up from another water bottle so we don’t suddenly run out of drinking water.
Watching our wee! It’s not uncommon for people to monitor their urine output and colour on expeditions. If we are passing urine, then we are flushing our kidneys of toxins and consuming sufficient fluids above what we are sweating. When we stop urinating, we need to rehydrate as soon as possible. Our wee should be a light straw colour and darker than light straw is a sure sign to rehydrate. What is a light straw colour? Well, it’s a similar shade to a yellow highlighter. Weeing to a small bottle often helps and common on expeditions enabling us to monitor our own health. Selecting a square wee bottle is easier to differentiate in the dark to avoid mistakes!
Being honest with ourselves and having the faith in those around us to identify signs of heat issues gives us the ability for early intervention which reduces conditions becoming worse, reduces the impact on the individual and allows us to flex our plans accordingly.
Hope this helps others have a lifetime of amazing adventures and get in touch with your own ideas. 😊
If sharing please include “shared from Wildcat Mountaineering Group page,
Chris Hobson has been a mountain leader for almost three decades, holds Winter Mountain Leader competence and has been on expeditions all over the world including the mountains and deserts of India, the greater ranges of the Himalayas and the European mountain ranges of the Alps and Pyrenees as well as working in all the mountain regions and seasons of the UK including almost a decade in UK Mountain Rescue.
