Learning to manage blood sugars when hiking is really important, and it takes a bit of trial and error to get it right. There are many things that will impact how blood sugars react to hiking and taking steps to anticipate these will make life a lot easier.

 

Distance, speed and elevation gain will all affect how quickly your body uses up available sugar in the blood. These three factors can often work together to drop blood sugars quickly and bring on hypos that are otherwise avoidable.

 

The length of a hike will obviously affect your blood sugar and insulin requirements. The further you go the more sugar, or the less insulin, you will need to maintain your blood sugar levels.

 

How fast you walk will also really impact your blood sugar levels. Walking quickly will drop blood sugars quicker than walking slowly, as walking quickly uses significantly more energy.

 

Elevation gain can sometimes be a forgotten consideration when it comes to hiking and blood sugars, with the impact of walking on the flat being considerably different to the impact of walking up a hill. Uphill walking uses much more energy and as such can have big and very sudden impacts on blood sugar levels. Blood sugars dropping quickly is common when switching from flat walking to walking uphill, with the steepness of the hill also a key factor.

When hiking these three elements often work together to drop blood sugars. Walking uphill, quickly, and for a long time is going to have a massive impact on blood sugars and is often responsible for unexpected hypos.

 

The other environmental element that will impact blood sugars in the terrain you are crossing. Smooth paths are easier to walk on and so you often move faster than on rocky, uneven ground. As speed impacts blood sugars, the difference in terrain will also play a role. When moving across rocky, boggy, densely vegetated ground, we tend to walk slower. The effort we use may be more but as the speed we move has decreased blood sugars don’t tend to drop as quickly.

 

When planning a hiking day out, it can be useful to investigate your route and consider the four factors mentioned above. A quick look into what the length, speed, elevation, and terrain of your day out is likely to include may highlight the likelihood of a hypo at various points during the course of the day. Knowing that a steep uphill climb is likely to drop blood sugars quickly can allow you to prepare for this, perhaps even pre-empting a drop by eating sweets. All of these criteria can be used to plan the best way to look after yourself and your blood sugars on your hike.

 

Everyone will of course react slightly differently to these environmental elements of a hike and so if you are starting out, shorter walks and smaller hills will give you time to learn how you respond to all of the factors and enable you to see patterns in your blood sugars. In time, this knowledge and experience will allow you to be confident in your ability to look after yourself on longer/harder walks.

 

How and when you take insulin is also an important factor in looking after your blood sugars while you hike. If your medical professionals are happy for you to make your own decisions about how much insulin you take it's worth considering dropping insulin amounts before and during hiking. Bolus insulin due to its fast-acting nature can cause severe hypos very quickly when out in the hills. As such it is worth minimising the amount of fast-acting insulin you need to take and timing your insulin to avoid taking it before higher effort parts of the day. For those taking basal insulin, it is often a good idea to reduce the amount of this you take on a day that you are hiking. Whether you reduce it and how much you reduce it by will be up to you and will often depend on the plan for your day.

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What you eat and when you eat it will have a big impact on your blood sugar levels and your enjoyment of the day. Fast-acting sugar such as Gluco shots, Haribo, sweets, glucose gel etc. must always be carried when out hiking. Things such as gluco shots and glucose gel will be used when hypo but having other fast-acting glucose such as Haribo or boiled sweets is important too. These can be eaten when blood sugars are starting to drop but not yet at hypo level, hopefully staving off a medical hypo.

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The other food you have in your pack will make a difference too. Having a mix of carby and non-carby options can make a big difference. When blood sugars are low and need to be brought back up again, chocolate, flapjacks, sandwiches etc are good options. When blood sugars are stable however these carby options will often mean needing to take insulin. While sometimes this might be fine, for example if you are about to start a steep uphill, this could also cause a drop in blood sugars (and perhaps a hypo) if there is a mismatch between the food being broken down and entering the bloodstream, and the time it takes for the insulin to act. For that reason, I would strongly recommend having some low-carb options such as nuts, dried meats (biltong, jerky, dried sausages etc.) on hand to eat when hungry whilst also preventing yo-yoing sugars.

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Keeping a close eye on your blood sugars is important and using a CGM can make life a lot easier from this point of view. Also for those who are using CGM’s setting the low alarm to go off BEFORE a hypo is a fantastic safeguard against hypos. Treating anything below 5mmol/l as a hypo can stop a real one from happening and save needing to stop and wait to recover.

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If a hypo does occur when you are on the hills, it is important to act swiftly. A severe hypo in a mountain environment can be very serious and increase the chances of having another in close succession. Stopping as soon as you go low and making sure you are fully recovered before you start moving again is really important. This is not always convenient, especially in bad weather, but it is important to be prepared to stop if needed to prevent endangering yourself or others. =

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Stopping for a hypo in good weather is not often an issue, maybe even allowing you some extra time to enjoy the views(!), however there are no safety considerations to make. Stopping in bad weather on the other hand, needs a little more planning. In cold, wet, and windy weather needing to stop is more of an undertaking. Getting cold quickly can be dangerous and so having spare warm layers, a waterproof jacket and hat and gloves is important. When travelling in a group, carrying a group shelter is another important piece of kit to have as it can provide important shelter and warmth on any unexpected longer stops.

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Most of the time you will be fine to continue once you have recovered from the but there can be days when blood sugars seem to have a mind of their own. If this is in combination with other extrinsic factors such as bad weather or tricky route navigation, then turning back is always the best and safest option.

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Like everything with Diabetes, there is a lot to think about when starting out but hiking and being in the hills is incredibly rewarding. Once you get used to how your body reacts it becomes relatively easy to look after yourself in the hills and have enjoyable days where diabetes has little impact. Spending a bit of time as you get started getting to know your body and your needs can truly make life a lot easier going forwards. We hope that this information helps you get to know your body as quickly as possible and be able to enjoy your time in the hills.