Protein Helps You Go the Distance
Protein-rich ultralight backpacking meals only get more important once you’re actually on the trail. In addition to keeping your muscles and other cells in good shape, protein also helps prevent muscle breakdown—which always happens during long duration exercise—and stymies fatigue.
Muscle isn’t a single-function organ. Yes, a muscle’s most important function is to enable movement, but it’s also a storage organ for amino acids, which can be converted into glucose in a pinch. This is important because our brain runs primarily off glucose, and it’s greedy. Not only does it consume more glucose (per ounce) than any other organ, but when glucose supplies start to dwindle (e.g., when we exercise) it starts to horde the remaining glucose for itself and tells the body to start making new glucose using our muscles as the fuel source. To a degree, this is inevitable, and not necessarily a problem.
When muscle breakdown occurs consistently throughout the day though, and each day is followed by a new day where it continues to happen, the body starts wearing down (sound familiar?). Dietary protein ameliorates this.
Your ultralight backpacking meals need to replenish amino acids—not only to repair the broken-down muscle tissue, but also for the brain to convert in the first place (carbs also help by preempting the need for gluconeogenesis, or new glucose creation). The body runs on signals, so if it detects high levels of amino acids in the blood, it gets the signal not to use muscle tissue and just use what’s available.
Protein also plays a role in preventing central fatigue, or brain fatigue. An interesting thing happens when our body starts turning amino acids into glucose: since our body can only use specific types of amino acids as the base for glucose, other amino acids—like tryptophan—become more dominant. As tryptophan gains dominance, it starts crossing the blood-brain barrier to a greater extent and forcing the brain to produce more tryptophan, which sends the signal to our body that it’s getting tired.
It’s important to note that this sort of fatigue is separate from muscular fatigue. Our brain and muscles give each other a ton of feedback, but in this case our brain is overriding what our muscles are saying. It tells our body that it’s so tired it doesn’t really care if the legs are willing to go on. Obviously, this isn’t ideal.
Thankfully, here again protein can help. While there’s a school of thought that advocates for intervention, specifically supplements containing individual amino acids like the BCAAs (branched chain amino acids), the actual results are poor-to-mixed.
Instead, keeping it simple with whole, high-quality protein produces results that are not doubted: during any exercise lasting longer than three hours, consuming protein along with carbohydrates and fat decreases fatigue and increases time-to-exhaustion.