Understanding Your Energy Needs: An Approach for Hikers and Trail Athletes

Nutrition can often feel like a complex topic, further muddled by the overwhelming amount of information available online. This complexity can quickly become overwhelming, putting you in the perfect position to be sold a ‘simple solution.’ But what’s wrong with simple solutions? The problem is that they are usually one-size-fits-all approaches to food and nutrition. Not only is it unlikely that this approach will meet your individual needs, but it’s also challenging to adapt when you’re in the field, on the trail, or during a multi-day thru-hike.

There are numerous ways to estimate your energy needs for hiking and other trail sports. However, it’s important to remember that these are just estimates. Even with the most detailed tools, the calculations are still estimations meant for planning purposes. While wearable technology can assist in determining energy needs, there’s a risk that the actual adventure—be it a hike, ride, or run—takes a backseat to your fuelling strategies.

Nutrition should fuel your activities, not overshadow them. When choosing a nutrition planning strategy, it’s essential to keep this in mind. As the intensity of your athletic activity rises, so does the need for precision in your nutrition. The more extreme the climate, terrain, distance, and intensity of energy expenditure, the more precise your nutrition needs to be. This also applies to the training and lifestyle you maintain while preparing for your event or expedition.

Hiking and multi-day events are unique from other endurance activities, which typically last between 2 and 24 hours. In those cases, you can push yourself to the limit and spend the next day recovering on the couch (though I don’t recommend that strategy). However, multi-day events require sustained performance day after day. Your recovery needs to be built into your performance strategy. The first step in doing this effectively is ensuring you meet your energy needs.

To estimate energy needs for multi-day events, I use METs (Metabolic Equivalent of Task). METs allow for a detailed focus on the energy requirements for a specific trail, for a specific person, and how they are hiking that trail. It also helps to account for energy needs off the trail, which is often overlooked in standard estimates—your body still needs fuel for the rest of the day.

METs also allow you to break down your hike into daily energy needs. You might encounter a particularly intense section with challenging terrain, move into a different climatic zone where it’s colder, or face a couple of really big days. All of these factors can be accounted for using METs.

How to Adjust MET Values for Accurate Energy Estimates on Your Hike

When planning any endurance activity, understanding your energy needs is crucial. One of the best tools to estimate these needs is METs. METs provide a way to measure how much energy you're burning during different activities, giving you a baseline for how much food and water you’ll need on the trail. But METs aren’t one-size-fits-all; they vary based on several factors, including your body weight, fitness level, terrain difficulty, weather conditions, and pack weight. By adjusting MET values to match your specific conditions, you can get a much more accurate estimate of your energy needs, helping you stay fuelled and strong throughout your adventure.

What Are METs and Why Are They Important?

METs are a standardized way to measure the energy cost of physical activities. One MET represents the amount of energy you use at rest—sitting quietly, for example. As the intensity of your activity increases, so does the MET value. For instance, walking on flat terrain might be around 3-4 METs, while hiking uphill with a heavy pack could be 8-9 METs.

METs are particularly useful because they offer a clear, quantifiable way to estimate how much energy you're burning. This can help you plan how much food you’ll need to carry and how much water you’ll need to drink. However, it’s important to remember that MET values typically only account for the energy used during the activity itself. Your overall energy needs also include the calories burned throughout the rest of the day—when you’re setting up camp, resting, or even sleeping. That’s where tools like my Hiking Nutrition Calculator come in, helping you estimate your total daily energy expenditure, not just what you burn on the trail.

Why Adjusting METs Is Essential for Accurate Planning

Standard MET values provide a great starting point, but they don’t always capture the full picture. Factors like your fitness level, body weight, the terrain you’re tackling, and the weather conditions can all influence how much energy you’re actually using. By adjusting the MET values to reflect your specific situation, you can make sure you’re planning accurately and avoiding the dreaded mid-hike energy crash.

Here’s how you can make these adjustments:

1. Body Weight and Fitness Level

• Body Weight: METs are typically calculated based on a person weighing 70 kg (about 154 lbs). If you weigh more or less, your actual energy expenditure will differ. For every 10 kg (22 lbs) above or below this average, adjust the MET value by about 0.5 METs. For example, if a hike has a standard MET value of 5.5 and you weigh 80 kg, you might increase the MET to 6.0.
• Fitness Level: If you’re very fit, your body is more efficient at performing physical tasks, which can slightly lower your actual energy expenditure. Conversely, if you’re just starting out or have a lower fitness level, you might burn more calories performing the same activity. If you’re very fit, consider decreasing the MET by 0.5; if you’re less fit, consider increasing it by 0.5-1.0.

2. Terrain Difficulty and Elevation Gain

• Terrain: The difficulty of the terrain has a significant impact on how much energy you burn. Hiking on flat, smooth trails may align with the standard MET values, but if you’re dealing with steep inclines, rocky paths, or loose sand, you’ll need to adjust. For example, if the standard MET for hiking on flat terrain is 5.5, hiking uphill on the rugged Bibbulmun Track might require a MET of 7.0 or higher.
• Elevation Gain: Elevation gain also plays a big role in energy expenditure. As a general rule, for every 100 meters of elevation gain, you can increase the MET value by 0.5-1.0, depending on the steepness and difficulty of the climb.

3. Weather Conditions

• Temperature: Extreme temperatures can increase the energy your body needs to maintain a stable core temperature. In hot weather, you might increase the MET by 0.5-1.0 due to the additional effort required to cool down. In cold weather, the body works harder to stay warm, so you might also increase the MET by 0.5-1.0.
• Wind and Rain: Adverse weather conditions like strong winds or heavy rain can make any hike more challenging. If you're hiking into a strong headwind or slogging through mud, consider increasing your MET value by 0.5-1.0.

Practical Application: Specific Examples by Location and Activity

Let’s apply these adjustments to some popular hiking and trail locations in Western Australia.

• Bibbulmun Track: This iconic trail offers a variety of terrains, from flat, coastal plains to the rugged hills of the Darling Ranges. If you're hiking a flatter section like the coastal stretch near Albany, you might stick with the average MET of 5.5. However, when tackling the hilly sections near Pemberton with a heavy pack, you could increase the MET to 7.0 or more, depending on the specific conditions.
• Cape to Cape Track: This coastal trail varies from sandy beaches to limestone cliffs. On easier, flat sections, the MET might be around 5.0-5.5. But as you climb steep dunes or navigate rocky paths, you could adjust this to 6.0-7.0.

Practical Tips for Using Adjusted METs

• Start with the Baseline: Use standard MET values as your starting point, then adjust based on the factors discussed above.
• Factor in All Elements: Consider body weight, fitness level, terrain difficulty, and weather conditions to fine-tune your MET estimate.
• Use a Calculator: Tools like my Hiking Nutrition Calculator can help you factor in these adjustments to get a more accurate estimate of your total energy needs, both on the trail and throughout the day.
• Consult the Compendium: The 2024 Compendium of Physical Activities is the online source for evidence based METs.

Looking Ahead: Adjusting MET Values for Pack Weight

In the next blog post in this series, we’ll dive deeper into how carrying different pack weights can affect your MET values, and how to adjust your energy planning accordingly. This will help you understand exactly how much more energy you’re burning when carrying a daypack versus a heavy backpack, ensuring you’re fully prepared for your next adventure.

Final Thought: Personalized Energy Needs

For those looking to fine-tune their trail nutrition strategy even further, consider booking an Adventure Initial Consult: Training & Event Strategy Session. This session will provide personalized insights and strategies tailored to your specific goals and needs, helping you perform at your best on every trail.

By adjusting MET values based on personal factors, you’re not just planning your hike—you’re setting yourself up for success, ensuring you have the energy and resources you need to enjoy the journey, no matter the conditions.

Not a hiker but looking to estimate your energy needs for trail running, mountain biking, or other trail sports? Check out the Trail Fuel Calculator here.

As The Adventure Nutritionist, I focus on teaching you how to develop practical, sustainable dietary practices personalised to your health and fitness objectives. With 25 years of experience as a coach and educator, I integrate solid scientific principles with hands-on expertise to empower adventurers, trail athletes, and busy professionals.

My mission is to cut through the noise of misinformation and provide you with simple, enjoyable approaches to nutrition. Whether you are preparing for a multi-day hike, a challenging trail run, or simply trying to balance a demanding career with your passion for adventure, I am here to guide you every step of the way.

Through personalised consulting, interactive workshops, and comprehensive educational courses, I offer evidence-based nutrition solutions tailored to your unique needs. Join me on this journey to optimise your performance, enhance your health, and achieve unstoppable success in all your outdoor pursuits.

Want to learn more about nutrition and hiking? Check out The Ultimate Guide to Nutrition for Hiking.

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