Hungry and drained during runs - looking for nutrition advice
I recently ran a 15k trail race (which turned out to be 16.5k) with 1,300m of elevation gain, and it took me 5h50m to finish. I felt strong until the second checkpoint at around 7.5k and 600m gain, but after that I was out of gas. The climbs were brutally steep and the terrain in general was very technical. I started getting hungry and dizzy, and ended up hiking the remaining course. Despite taking five or six gels, my body constantly screamed for actual food. Then, for the next five days despite doing nothing but resting, I was absolutely ravenous. No matter how much I ate, I still felt hungry all the time.
This was my longest trail run and also the biggest elevation gain I’ve done. Before this, my usual trail runs were around 9-10k with up to 450m gain without gels., which usually required a recovery day afterward.
I’m wondering if being underweight might be part of the issue. I’m 34F, 164 cm (5’4”) and 46 kg – basically the same weight I’ve been for the past 20 years. I even tried eating more than usual in the days leading up to the race, but after nearly 6 hours on the trail I felt like I’d burned a week’s worth of calories lol. As for my weekly fitness routine, it's a mix of strength training (mostly bodyweight exercises) and running on flat ground – three times a week. I’ve also completed a half marathon at an average pace of 6:30/km.
I can bring more gels next time, but honestly they only seem to help for about 30 minutes before I crash again. I’d really like to finish stronger next time instead of fighting for my survival and then feeling hollow for several days post-race. Any tips on improving energy levels and endurance would be greatly appreciated!