So I ran my first ultra last year, the VT50. Earlier in the year, from April through June, I built my miles up with my long runs at around 3 hours. I tried to keep my heart rate below 155. At that point I bit on the low heart rate training mentality and gave that a swing for the next 10-11 weeks till VT. During my three hour long runs earlier I started to get nauseous towards the end. Duiring my low hr training, I ran a 50K and a 26 mile training run and didn't experience any. During the last 15 miles of VT, I got very nauseous. I ran the whole race at heart rates of 150-165. All that is an aside but lets you know the thinking behind my question. What do you all think of the idea of doing all my training at heart rates between 150 and 160, except for maybe slowing down on longer runs, just running easy? My thoughts are that my body will adapt to running in that heart rate range and will be more efficient at eliminating wastes and making for more comfortable races. I hypothesize that my nausea was due to metabolic stress and waste buildup. Still trying to figure the whole thing out as I thought I had my nutrition down. Another question in that vein: does HEED have electrolytes in it? That's what I drank during VT. Let me hear y'alls thoughts on the training question. Thanks.