Our teammate, Derek Thornton, sought to end a breakthrough season of short-to-mid distance time trials, of which he PB’d several times with little-to-no-aid (because, COVID), by aiming to run more mileage in 1 week than he had ever run before – the always sexy, round 1-0-0. Below is an account of his first ever 100 mile week, which he accomplished last Sunday, 5/31. Note – his previous most miles run in 1 week = 70.

What it is like to double your weekly mileage and run 100 miles in one week?

I’m not what most would call a high mileage runner. It was only last year when I started running 50 miles per week (mpw) regularly. When COVID started and races were cancelled, I knew I had to point my naturally competitive nature in some direction. So, for a new challenge to stay motivated I got the idea to run 100 miles in one week to end my season. Many of my teammates do this much mileage regularly, but I had only topped 70 mpw a handful of times in my life, most recently last fall during peak marathon training for the Snohomish Marathon. Since there won’t be any racing for the foreseeable future, I thought it wouldn’t cause too much FOMO if I got injured in the attempt. But let’s start with the obvious question:

Why run 100 miles in a week?

From my viewpoint, there is nothing magical about this very arbitrary number. Why not 100k? Why not over 10 days? While it’s arbitrary, technically, all running goals are/can be. I decided to do it mostly for the same reason most people run their first marathon – to say I did it. I understand that many people run more miles regularly, but for me this was going to be a stretch – I’d need to double my current weekly mileage.

I suffered a major injury in college partially by running a lot of miles (for me at the time), and have kept that piece of information close to me when deciding on how much volume to run. So it was an underlying motive to suss out exactly what I’m capable of with the hope that in accomplishing 100 miles, I could challenge my fear that higher mileage leads to injuries. Finally, I thought it would push my limits and improve my running. I loved the show, Pros vs Joes, and wondered if this would feel a bit like I was going up against something far beyond my talent level. Well, here’s what it was like for me day by day –

Monday (Memorial Day): 20 miles in the rain. The first 8 miles were with a couple other people. In planning out the week, there were 3 days that I thought might be the hardest to endure, and this was one of them. I hadn’t run more than 15 miles in over 6 months; I thought it would be a bit of a stretch. I felt surprisingly good when I finished. Overall, I didn’t feel drained like I usually do after a 20-miler. A shockingly good start.

Tuesday: 8 miles before work + 7 miles at lunch for 15 total miles. I felt yesterday’s miles in the first run at 6 am; started to question how this was going to turn out. I think it was the early morning and stiff muscles combined with the rain, because the lunch run felt way better (plus it was sunny). Mentally I still felt alert and although my legs felt tired, I was hoping that by delaying tomorrow’s run til after work, there’d be more time to recover between.

Wednesday: 12 sunny miles after work. I’ve been working from home like many people and needed to go to the office to sign a few things. Afterwards, I decided to run down by the bay because it was a gorgeous day. Little aches around old injuries and weak spots in my legs began to show. I hadn’t had lower back pain in years, but I started to feel some pain there today. The views were great, but I can’t say it felt better than just ok.

Thursday: 10 miles before work + 5 miles at lunch for 15 total miles. This was another one of those days I thought might be “dark.” There’s a saying that “your farthest from the finish not at the beginning, but in the middle,” and I was worried the cumulative fatigue on a double would get to me this day. A good friend who has done many a hundos said to try and split the double less evenly and put more time between each run. With work and a family, I couldn’t change when I ran, but I could get up a bit earlier and get more miles in then. A PT also reminded me to do extra foam rolling and stretching. These pieces of advice helped this day feel better than expected. The shorter lunch run was still a grinder and my rolling 7-day miles were over 80 (a new record for me). I felt the cumulative fatigue but it was manageable.

Friday: 8 miles. The “shorter” day was a welcomed change. I started to notice a bit more mental fatigue on this day and had to make sure to re-read those work emails to make sure they made sense. The minor aches started to subside with less miles on the day, but major muscle groups were still tired. I tied my weekly mileage record and it helped to know every step after would be pure profit.

Saturday: 10 miles. After 2+ months of almost entirely solo running to be as respectful as possible to the vulnerable people in our community, running with a couple people was a welcome respite. I joined a group run broke into small groups of 5 or less. I felt a few hip muscles twinge for a few moments that gave me concern, but otherwise this felt like a normal tired run. The fatigue was still there, but also the thought of setting a new personal mileage record gave a bit of a mental lift. Knowing tomorrow was another 20-miler made me feel a bit like Frodo as he got closer to the end of his journey and the weight of the burden became more intense. Would I make it, or would an injury pop up last minute and ruin my adventure?

Sunday: 20 miles. Success! Honestly, it was also a bit anticlimactic to finish. Allison and Kennedy were running 24 for the day and I joined them. They gave me kudos when I finished, but they also added on another 4 miles after I finished… I felt good enough that I could have joined them and even contemplated it, but I was satisfied with what I had accomplished so I calmed the competitive nature for the day. In the end, I thought it was probably an appropriate end for an arbitrary personal goal; the satisfaction must come from within. At night, my legs and joints certainly were achy or tired but the next morning I felt like I could go for another easy run. Instead I did a short walk with the family and some gardening.

I thought I would share a few surprises and lessons learned to end this recap.

• I never got uber hungry, and if anything, I felt like my appetite was a bit suppressed. This surprised me but makes me wonder if it will hit next week.
• I still don’t ever plan on doing this again, but if I did, I wouldn’t try to front load the mileage quite as much. In hindsight, I should have done my 8 mile day, then 12 miles Thursday and a 15 mile double Friday for better recovery.
• I thought I would only be able to do this on a holiday week, but I now think it’s possible to work 5 days and run 100 miles without sacrificing too much additional time with the family. One week of 100 miles is much more doable than I realized. I also agree with many others – that stacking multiple in a row would be much more difficult.
• Old injuries and weak spots I hadn’t dealt with in years came back. I had to take extra care each day to keep from feeling worse. The attention to other details became much more instead of just being able to focus on the added miles. Not surprising, but I saw some random aches and pains comes up that I’d never had before too. I also had more heartburn than normal on my runs, which may have been related or coincidence.
• I rarely felt like I couldn’t run more or pop off a solid workout instead of easy miles, but there was a very different type of fatigue I felt by mid-week that continued through the rest of the week. A small but steep hill coming up from Squalicum Bay trail to Eldridge Road on Wednesday’s run felt like I was warming up at 4k feet of elevation for Ski to Sea and could never fully catch my breath. I had never felt fatigue like this before and didn’t expect the tiredness to manifest itself this way. I have a new appreciation for my teammates who do this regularly, and even more for those that add a lot of vert too!
• Lastly, it reminded me that there are two levers to running. I believe that you can lessen one while increasing the other and still be ok. For this week I dropped all intensity and spiked the mileage and it didn’t destroy me. I can’t, or maybe just don’t want to, imagine doing this many miles with the intensity of workouts added.

I plan on taking the next week off. I am still human and still have irrational injury fears, so I don’t want to push it too much. I do firmly believe that pushing my aerobic base like this will help me in the fall even if we don’t get to race each other. I still don’t think that it’s a life altering accomplishment, but I am glad that I checked this off my running list of things to do, and the satisfaction is worth it!

PS: Thanks to teammates, friends, and my family for all the encouragement, miles, tips, and sacrifices you made so I could accomplish this goal this week!

Derek Thornton