- Karl Etzel's Newsletter
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- June 2023
June 2023
Plyo, monetary / fiscal policy, D2C presidential campaign, training intensity, trail races
Alex Hutchinson at Outside magazine published an article recently on plyometrics and their impact on running economy. As you may recall from my plantar fasciitis edition, I have been doing more plyo in my warmups. If you want some practical advice, this video I came across on Twitter has a really good warmup routine that I’ve been sampling from heavily. Takeaway: a little bit goes a long way. Plyo is high ROI.
Regular readers know I’m a fan of Stanley Druckenmiller. He recently gave a keynote and reiterated some themes he’s been talking about for years regarding entitlements, government debt, and monetary policy. You can find the transcript and notes here. It’s worth a read.
As I make a slow, steady return to running after a layoff due to PF, I’m starting to let myself think about goals. I’ve become mildly obsessed with the Softrock 100, which is the multi-day fastpacking version of the Hardrock 100, a famous ultra in the San Juan mountains of Colorado that loops through Silverton-Telluride-Ouray. Doing it as a multi-day means covering the distance at a faster pace, enjoying a relaxing hot meal and warm bed every night, and getting to see all the scenery since racing it straight through means covering a lot of mileage in the dark. Obviously this is a 2024 goal given where I’m at in my training progression. If you’re curious about my planned mileage progression I posted it here. I have the Mammoth Dragon’s Back Ascent penciled in for this September. At only 2.75 miles, straight uphill, it will stress my lungs more than my feet and should be a great weekend in the mountains watching the Golden Trail World Series.
Continuing the theme around politicians sidestepping the MSM, this time from the other “side of the aisle”, Ron DeSantis announced his bid for the Republican nomination on Twitter. Predictably the MSM declared DeSantis’ campaign dead before it started due to technical glitches when Twitter Spaces crashed, overloaded by about 1M people trying to join. Frankly I’m surprised it’s taken politicians this long to bypass the talking heads and go straight to the voters on social media. Roosevelt did it with his famous fireside chats in the 1930’s. Once again - I’m not arguing for or against DeSantis. I’m arguing for thorough, substance rich coverage unfiltered by a biased media. I’m delighted to see any candidate from any party bypassing the MSM and going straight to the voters.
In my series on training, this month I’ll talk intensity. First thing to keep in mind is that high intensity work racks up the TSS points a lot faster than Zone 2 , as the relationship is not linear. For this reason, overtraining is more likely to occur if you overdo it on intensity than if you overdo it on volume. IME there’s likely some social dynamic to this as well, as the motivation and drive of a group workout or race can easily induce an athlete to spending too much time going hard. This is also why Zwift is a culprit in many athletes overreaching or overtraining. The good thing about Zwift (it’s super engaging) is the bad thing about it (in the limit, engagement becomes addiction). Dr. Stephen Seiler conducted much of the early research on optimal training balance, and you can learn more about it here. The takeaway: Zones 1 & 2 should dominate your training distribution, with 20% or less of your time in higher zones. If you’re piling on the HIIT, Zwift races, and Orange Theory workouts all week, you are not setting yourself up for long term success. This graph in TrainingPeaks of my rolling 7 day HR zone distribution is one of the 2 or 3 that I most rely on to guide my efforts and choose my workouts. Next month I’ll cover how I map out each week to hit these numbers.

Finally, some of you may know I recently got laid off from Exos. For the moment I’m staying reasonably occupied (i.e., I’m working 20+ hours a week, not 60+ hours a week) with a few consulting projects and working part time with Runday.ai, an AI startup bringing the power of generative AI to the challenge of engaging customers 24×7 and scheduling appointments. It’s been great to take a break and get re-connected with many old friends and colleagues from across the industry, and I’m looking forward to what’s next for me in the health and human performance space.
One of my favorite places to go running, Cliff Drive in Santa Cruz.
