I set out to run 16 miles yesterday, after having run 14 and 15 in the past few weeks with no issues. The 15 mile run (last weekend) went great actually, HR stayed 128-131 until I pushed the pace at mile 12.
I went out yesterday, it was in the low-70’s and sunny. I didn’t really have anything to drink beforehand except some OJ with a bagel. I did have my Fuel Belt with 50 oz. of Gatorade with me on the run.
My HR was higher than last week (actually, as sometimes happens, it was oddly high (e.g. 170’s) at even an easy pace at the very beginning, would “correct” if I walked for a few seconds to manually check my HR). But I was trying to push the pace by a little, but still pretty easy. HR was often in the 150’s.
Anyway, I was planning on pushing the pace up to marathon goal pace over the last 4 miles. But at 11.5 miles my legs just felt so fatigued. Within minutes I was walking. I ran/walked for 3 more miles. I’d feel OK as I started to run, then boom, all energy would be gone. Had to walk home the last 1.5 miles.
I had drank approximately 36 ounces of Gatorade over the first 11 miles (for me almost 2 hours).
I got home and crashed on the floor. Drank a lot of fluids. Felt very chilled. I lost about 8 pounds on the run and walk home. Almost 4% of my body weight. Had salt deposits on my forearms…never seen that before.
I plan on being much more proactive with fluids before and during my next long run. But…is it likely dehydration led to this? I’ve read about it huting performance by X%. Can that level of dehydration lead to the inability to continue running? I don’t think I was “bonking”, between the bagel and the Gatorade I certainly should have had enough fuel for more than 2 hours of activity.
Does it sound like dehydration was the culprit? How many ounces of fluid can you guys consume while exercising?
Thanks.
Jeff