August 2024

Happy to get this newsletter out before August 31. You can already tell the days are getting shorter and there’s occasionally a hint of fall in the air here in NorCal.

I recently did another round of lactate profiling on the bike. It's a lot easier with modern tech, I use TrainingPeaks to create a custom workout with the necessary power ramp, then I send that to Garmin Connect, which loads it on my Garmin Edge 530. In Training / workout mode the Edge controls my Wahoo KICKR so I can just turn the pedals, and focus on the sample collection. I prep all my strips on cotton pads and just drip alcohol on the pads from a tiny Nalgene bottle. I use a lance which can be cocked and fired with one hand. I’ve gotten pretty smooth at doing this in the garage and the lactate meter has been a great investment.

In the end I get a plot like this, you can see my last 4 tests all line up pretty well, which is actually good since I’ve been on the bike so little this year. I haven’t lost much ground and for my Zone 2 rides (I target about 8 hours a week here) I hang out around 150W/2.0 mmol/L and for tempo (1.5 ours per week) 180W / 3.0 mmol/L.

Weight loss in some sense is very simple - just create and maintain a calorie deficit. In practice of course it’s more complicated. The current craze in obesity treatment (GLP-1s) works on one side of the calorie balance by suppressing appetite so you eat less. There’s a generation of drugs coming that work on the other side of the balance and cause you to burn more calories. This was tried long ago with DNP, which got pulled from the market after a number of deaths because it made people essentially overheat themselves to death. There are still unscrupulous people selling it today, and it is very dangerous. Do not, under any circumstances, consider using DNP. The next wave of drugs in development is much smarter and take a more targeted approach to increasing energy expenditure. Of course you could always just put on a few more pounds of muscle mass and let that drive your metabolism up, and get numerous other benefits of more muscle, but we do love our drugs here in the US.

John Speakman is well known in the energy research world as one of the experts on doubly labeled water, and he recently published a paper on coffee and the variety of bioactive compounds in it that affect energy. It’s not just about the caffeine. Have a look if you are as interested in coffee as I am.

As you know creatine is one of my core supplements, I recently learned Thorne creatine is no longer sourced from Creapure, which is generally regarded as the best in the business. A colleague experienced some GI issues with it, which caused me to look into their supplier. Just an FYI in case you are a regular Thorne user.

We can debate which trail race is the greatest or the hardest but in terms of spectacle, there is no debate. Ultra-Trail du Mont Blanc (UTMB) is later this month and you can catch the action live on the internet here. It’s actually a week of racing, with multiple events over different distances. I can’t wait.

More from my Colorado trip along the Hardrock100 course: