You’ve been training for that long hike for months by eating healthy, exercising, and doing everything you can to prepare for such a long hike. Now that this hike is over and you have gotten back to your regular routine, you hop on the scale and realize that you actually gained weight. Why did this happen? Let’s see why hiking and weight gain might be related.
Some hikers may experience weight gain because of an increase in water weight, an increase in muscle mass, or because of a rapid intake of high calorie foods.
We asked the hiking community if they experienced weight gain while hiking. While we did not get the answer we were looking for, other research gave us some insight as to why weight gain or hiking might be linked. There are a couple of ways that we could approach this, mostly we will analyzed how exercise and weight gain are related.
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Hikers Respond: Did You Gain or Lose Weight on a 16+ Mile Hike?
We were curious about whether or not hiking truly makes you gain weight. While some evidence does shows that you can replace fat mass with muscle mass, we wanted to know what the public and real hikers experienced. So, we asked the hiking community if they gained or lost weight on a 16 or more mile hike.
While some people do experience a weight gain, most people either stay the same (47%) weight and 38% of the same group lost three to four pounds.
However, we always have to talk about the potential biases of these surveys and also how 16 plus miles is a rather ambiguous number. We didn’t really figure out if these people were right around 16 miles, did a thru hike in the Appalachian Mountains, or if these respondents truly measured their weight that carefully.
| Did You Gain or Lose Weight on a 16+ Mile Hike? | Number of Responses | Percentage of Total Responses |
| Lose 5+ Pounds | 3 | 2% |
| Lose 3-4 Pounds | 55 | 38% |
| Lose 1-2 Pounds | 11 | 8% |
| Stay the Same | 68 | 47% |
| Gain 1-2 Pounds | 6 | 4% |
| Gain 3-4 Pounds | 0 | 0% |
| Gain 5+ Pounds | 2 | 1% |
Does Hiking Make You Gain Weight? Reasons Why You Might Gain
Most people lose weight when hiking long distances–but not everyone. The most common reason people gain weight (especially on a short trip) is due to a gain in water weight.
However, it’s a little more complicated than that. When we exercise, we are working our muscles and trying to make them stronger. That being said, exercising may involve turning your fat mass into muscle mass.
One of the main reasons that you may experience weight gain when you exercise is because you are likely converting your fat mass into muscle mass. Before we can even dive into the specifics, it’s important to explain the difference between fat and muscle.
Muscle is denser than fat. This means that if you were to hold the same amount of fat in one hand as muscle on the other, you will likely notice that the muscle weighs more than fat. A good visual of this is to imagine yourself holding a bucket of marshmallows in one hand and a bucket of bricks in the other. Which one is going to weigh more?
If you answered the bucket of bricks weighs more, then hopefully the difference between fat mass and muscle mass makes a little more sense. This is also why an extra 20 pounds of fat may appear soft and less toned than 20 pounds of muscle typically looks firm and sculpted.
Muscle also serves a drastically different purpose than fat does. While fat is used to insulate your body and trap in heat, muscle boosts your metabolism. Thus, the more muscle you have on your body, the more calories you burn during regular activities. And, the hungrier you are. The more calories your burn, the more you need to eat. It’s as simple as that.
When you exercise, you are working your muscles and attempting to strengthen those areas of your body. Your body is adapting to these new physiological changes and usually results in the formation of muscle mass. This is why even marathon runners may experience weight gain as they are undergoing their intense endurance workouts.
As you lose fat mass, your body will increase its muscle mass. When this happens, you will likely start to gain weight. But there are also some other reasons why you could be participating in endurance exercises, such as hiking, and still gain weight. We explore some of these in the sections below.
Water Weight: the Most Likely Culprit for Post-Hike Weight Gain
You have likely heard that increasing your carbohydrate intake, also known as “carbo loading,” is what you should do when you participate in any sport or endurance activity. For that reason, carbohydrate loading is a common practice done among athletes and non athletes alike. (Although experts disagree whether this works or not)
When you do start an endurance training program, your body can actually increase its ability to store muscle glycogen by 60% on up to 70%. This increase may also lead to perceived weight gain. In an article about carbohydrate loading, researchers found for every ounce of glycogen you store in your body, the body also stores about 3 ounces of water. This is what they mean by water weight.
So, when you step on the scale and expect to see weight loss, you may actually see that you have gained weight. Particularly if you drink a lot of water, the weight gain may be significant. Water weight will also fluctuate each day and even by the week.
The water weight itself is not actually your true fat mass and weight, but it is weight that is simply caused by stored water. You should also remind yourself that storing extra water and glycogen are good for your body because it can help give you the energy you need when you go on those more intense hikes. That said, storing glycogen is not a bad thing, but the quick “weight gain” can seem alarming.
Overestimating Your Calorie Needs
Hikers may overestimate the number of calories they need to eat after a hike. While you are burning a significant number of calories per hour, it still is not the best idea to eating entire pizza after an afternoon hike. The number of calories that you burn is highly dependent on your way to, the intensity of the hike, the length of the hike, and whether or not you are carrying anything on your back.
Furthermore, hiking food is absolutely packed with calories as we’ll see below.
Even your own body weight and metabolism impacts the number of calories that you burn. For example, if you are an experienced hiker who goes on numerous hikes each week, you may not need to exert as much energy as someone who only hikes every couple of months. This is because your body is used hiking and has already built up the muscles needed to be successful on your hike.
Another problem with overestimating your calories is telling yourself that you earned some extra treats that day. While it’s absolutely true you deserve a reward after or during a hard hike, this is a common reason why hikers gain weight. So if you’re trying to watch your weight and use exercise as a reason to eat more, it could lead to unintentional weight gain.
Gains In Muscle Mass To Blame For Post-Hike Weight Gain
Even endurance sports, such as hiking and distance running, can promote muscle growth. Particularly in your legs and buttocks, you may notice more toned muscles and increased muscle strength. As we mentioned above, muscle is denser than fat which means the muscle will weigh more than the same amount of fat. In fact, one liter of muscle weighs about 2.3 pounds (banister nutrition) while one liter of fat weighs about 1.98 pounds.
Additionally, many people think aerobic exercise like hiking only improves your heart and lung health. However, one research study (source) found that endurance exercises (like hiking) actually increase skeletal muscle mass and actually does have increased amounts of the proteins that promote muscle synthesis (the building blocks of muscles).
Managing Calories While Hiking
It seems like it should be simple–hike more = more weight loss.
However, managing your calorie intake can be a delicate process, especially for certain people. These are a couple of the main things to be aware of:
Not Eating Enough During Your Hike
Some people experience the phenomenon of not being hungry while they exercise or even in the time immediately after your hike. However, not eating or consuming calories may end up leading to unintentional weight gain. This is because the longer you wait eat, the more your body starts to crave high calorie foods that are high in sugar and excess calories.
Because fatty foods supply the most energy, it’s natural that our body will crave these after we expend so much energy. However, giving into these unhealthy cravings may not be the best choice if you are trying to monitor your weight.
If you are that person who waits a couple hours to eat after you hike, you could make some unhealthy food choices that might not be the best for your health. While we’re not saying you should have skipped the heavy breakfast after your hike, it may be worth it to eat a granola bar during a hike or right after it to help curb your cravings.
Hiking and High-Calorie Snacks
One factor that may go into gaining weight after a hiking trip is the foods that we eat while hiking. Because we have to pack as light as we can, hikers typically aim to bring as many high calorie and light weight snacks as we can. That said, we often consume quite a bit of these high calorie snacks and may not know how many calories we’re eating.
Even though hiking can burn a lot of calories (anywhere from 300 to 800+ an hour) and we do need to replenish our calorie supply, we can easily eat too many calories in one sitting which could potentially influence our weight fluctuations. Let’s face it, you can easily knock down an entire package of jerky and a large handful of nuts in one sitting. But how many calories is that? Below we summarize the average calories for some of the more popular hiking snacks.
| Snack | Serving Size | Average Calories |
| Granola Bars | 1 bar | 100-300 calories |
| Protein Bars | 1 bar | 150-400 calories |
| Nuts and Seeds | 1 ounce | 128-204 calories |
| Dried Fruit | 1 cup | up to 480 calories |
| Fruit Snacks | 1 pouch | 80-130 calories |
| Jerky | 1 ounce | 60-107 calories |
| Nut Butter | 1 tablespoon | 80-100 calories |
Body Changes After Hiking That Can Lead To Weight Gain
If you finished up a big hike, your body can actually do several different things, some good, some that you have to manage. Hiking overall is good for us mentally (check out my article where I found several studies to support this), your body’s changes in appetite and hunger can be concerning if you are watching your weight.
Immediate Changes in Appetite: “Hiker Hunger”
We do have an entire article on why you are so hungry after hiking, but it is worth it to discuss hike hunger in this article as well. Being really hungry after a long hike is normal. When you hike, you can burn up to 300 to 800+ calories each hour. This is a rate that is nearly 500% higher than activities that we’re used to (like working on the computer, or driving)
Especially if you are carrying weight on your back during your hike, you may find that you are incredibly hungry after a long hike. This is because hiking burns more calories than you think, and you are likely not eating enough calories while you hike. If you are backpacking, the “name of the game” is to carry as little as possible, so you likely aren’t carrying a ton of food.
As you hike, your body begins to adapt the new level of physical activity and requires more calories. Even after you are done with your hike, your body still craves the higher level of calories. That said, you may still crave more calories or higher calorie foods four days after your hike as your body begins to readjust back to your normal routine.
Want to learn how to avoid hike hunger and how to make sure you are eating enough on the trail? Make sure you check out our article on hike hunger.
Long Term Changes in Appetite
Many hikers report that they have an increased appetite for days and even up to a week after a long hike. Alternatively, some hikers actually experience a decrease in appetite. Why does this happen? While there could be several reasons that you aren’t hungry on a hike, including changes in your schedule, not being interested in the food you brought, or simply being mission oriented to finish your hike, it simply may also be due to the fact that hiking is an endurance exercise.
If you are one of the people who feel nauseous or not hungry while you’re on a long hike, you may not be alone. As we mentioned in our hiking hunger article, endurance exercisers don’t feel hunger (runnersworld) pains immediately after exercise when compared to those who do high intensity and short workouts.
If you do find that you are really hungry after a long or even a short hike, it’s likely simply because you experienced a metabolism boost, didn’t get enough calories on your hike, or didn’t have a big enough breakfast.
Because your appetite has been boosted after your hike, you may find yourself eating a lot more food or foods that are higher in calories than if you didn’t go for a hike. Because your body is likely trying to account for the calories that you missed out or burned while you were hiking, you could accidently overeat which may lead to weight gain if you are not normally active.
Metabolism After Hiking
Our bodyweight and the amount of calories we need to eat is impacted by several different factors. The combination of our genes, environment, and daily activity all makes up the amount of calories that we need to intake in order to balance out the calories that we expend. This is called a metabolic rate (lumen learning) and is defined by the amount of calories that we need in order to have energy to perform tasks.
Those with high metabolic rates tend to burn off more calories than people who have a lower metabolism. After hiking, you may see a spike in your metabolism because of the constant movement, carrying heavy weight, and the fact that your body needs to adapt to external temperatures.
In fact, even a short hike can give you a boost in metabolism. Some sources say that even up to 14 hours after your hike (emetabolic) your metabolism may be increased and you may feel hungrier than if you had just sat at your desk all day. This is pretty normal and can be expected after any hike regardless of length.