Heat Protocol from a World-Record-Holding Middle Distance Runner

I began heat training because I wanted to see if it was beneficial for a middle distance runner. I was curious to see how it comes into practice within the structure of a training week. As someone who lives and trains at sea level, I was interested in achieving the metabolic gains of training at high altitude while remaining at sea level. These aspects were all questions when I started this process in October 2025. 

My coach, Tom Nohilly, and I came up with one rule this year when implementing heat training:Do not let it affect the other sessions of the week. We had to find a way to implement this new strain without it having a negative impact on the training for the week. 

Heat during recovery days 

I would often use my recovery days in the week as heat training opportunities. For example, on Wednesday morning I would go for an easy distance run on a treadmill. I ran as easy as I needed to in order to recover from the previous day's training. Being on the treadmill allowed me to have an elevated skin temperature and core temperature relative to running outside.   

When I finished my run I would put on dry clothes and the CORE Heat Training Suit and immediately get on the spin bike. I would spin for 30–40 minutes to maintain the heat I had produced on the treadmill. This would help increase the Heat Training Load to the goal number for the day, without putting too much physical or aerobic strain on my body. 

I was able to maintain the goal of the day which was to recover, all while pushing the heat gains. I would find these “combo sessions” useful for improving my heat adaptations. The first few of these were difficult, but like anything, they became easier the more I did them.   

My goal for these sessions was to achieve a Heat Training Load of 3.0–6.0. For a combo session the aim is to be on the higher end of this range, and for a pure heat training session on the bike it would be the lower end of this range. The goal Heat Strain Index score I would aim for during these sessions would be a maximum of 4.5 HSI while exercising. I found that anything higher than this value would compromise the next day of training.  

One month to Heat Champion 

I found that in the adaptation period, this level of heat training 2–3 times a week helped boost the adaptation score fairly quickly. I was able to get to Heat Champion (over 90% adapted) within 1 month of using this protocol.   

I maintained Heat Champion status for over 3 months. To maintain the adaptations I kept 2–3 heat sessions a week in my schedule, but I kept the HTL no higher than 4.0. The maximum HSI level would be slightly lower, in a range 3.5–3.8. I would aim for one bigger heat training session with an HTL of 7.0–8.0 every 10 days to challenge the body slightly. This is to make sure the stimulus was still present during a “lower load” of heat training.   

There is more than one way to heat train as a middle distance runner. Similar to the alternative training styles for these disciplines, everyone responds differently to certain stimuli. I chose to cross-train for the majority of my heat training because it was the most effective way to implement it within the structure of my week.  

Other opportunities include running with layers on a treadmill, choosing to run at the warmest part of the day in layers, other styles of “combo sessions”, etc. These are all options I have tried, but I found that building it around the important aspects of the week was the most effective way to include it within my training.   

The other option would be to use “passive heat training”; options such as sauna, steam room, hot bath, etc. These are all great ways to improve heat adaptation outside of normal training. I used passive heat training opportunities more when I was at altitude since I was in a maintenance phase of my heat adaptation while heading into racing. Using passive heat training options directly after a heat training session is the best way to top off and maximize the session.  

Example: 60 min cross train with layers, and finish with 10–20 minutes in a sauna.

During a training block at altitude I was able to maintain my heat gains. I arrived in Flagstaff, Arizona with a heat adaptation score in the mid 90% range. The only adjustment that was made was backing off the active heat training from 2–3 sessions a week to 2 sessions a week maximum. This training block was dedicated to sharpening up for the indoor season, so there was less cross training implemented into my training.  

In fear of overtraining during this block, my main source of maintaining heat adaption was passive heat training. I decided to implement 3–4 dry sauna sessions a week with a duration of 15–20 minutes each. One of these sessions per week was tacked on to the end of a combo session. I was able to maintain over 90% heat adaptation with the implementation of passive heat training at altitude.   

I have seen positive gains physically, aerobically, and mentally since implementing heat training. Physically I felt like my body was recovering much faster than before. The elevated body temperature allowed me to get better blood flow throughout my body on a consistent basis. I had my most consistent block of training, and it was the best I had felt carrying a large training load.  

I made great aerobic gains during this initial block as well. I watched my heart rate ride lower as the paces picked up in training. This allowed me to push more and stay within the lactate goal of any given session. Even for harder track intervals I felt strong both physically and aerobically.  

My recovery had never been better for that point of the fall build. I really enjoyed the mental push heat training has given me as well. It has taught me to be comfortable with being uncomfortable. I put myself in uncomfortable conditions multiple times a week and it allowed me to become mentally stronger. I began to enjoy the uncomfortableness that came with heat training, almost to the point where it felt like I was going for another easy run.