Race Report: Big Chief 50K

Happy to run my first organized race, the Big Chief 50K, in over a year!

It was a great learning experience as I could assess different variables that impact performance. I was monitoring my glucose levels via my continuous glucose monitor and my heart rate via my Garmin watch, all while being mindful of how the overall elevation (6,500-7,800 ft above sea level), elevation gain(>4,000ft), and heat (90+ degrees) impacted my glucose levels and heart rate.

I don’t follow many traditional running rules. There’s a lot of thought behind what I do. I dive into that, my overall experience of the Big Chief 50K, and other topics below in my blog post:

  • Why athletes like Eliud Kipchoge are using glucose monitors to prepare for races
  • The best time to fuel during your race. It’s not pre-race as that and the onset of exercise causes a blood sugar crash immediately
  • How my glucose monitor impacted my fueling and race strategy
  • Two startups (Levels Health and Supersapiens) and their differing philosophies for maintaining healthy blood sugar levels
  • Why I stay away from most gels and how the steady glucose impact of UCAN gels helped my performance
  • How the elevation impacted me and how I used my (surprising) heart-rate data to determine my pacing
  • Why I started my ultra with an empty hydration pack, and
  • My overall experience from the Big Chief 50k!

Overall race:

First off, this was a beautiful course. The Big Chief 50K begins at Northstar Resort as you begin to run up the hills alongside the ski lifts. The race has a very early first aid station at mile 3, which Kathy volunteered at! Thanks for coming out and hyping up all the runners – definitely a boost of energy after our first hill!

Big Chief 50K elevation
Elevation Chart, Big Chief 50K. Aid Stations at Mile 3, 11, 17,23, 27

The early miles are some of the steeper climbs of the race prior to mile 25. It’s well shaded during the early part of the race (before it gets hot), while the hills at mile 25 (when it actually is hot) are fully exposed. Yikes.

After mile 7, you see some great views of Lake Tahoe. Some point after mile 15, you run into some really technical parts where you’re running over granite and small rocks. While my original goal was to run an 8 hour race, I finished the first half at 3.5 hours and thought maybe I could push for 7hrs.

Sawtooth Trail, Big Chief 50K
Sawtooth Trail, Big Chief 50K

You get a gradual decline from mile 16 to 25, which all seemed a breeze to me. But with me taking my time at the aid stations, I realized it was best to change my goal to 7.5 hours.

The part of the Big Chief 50K that I dreaded was mile 25 on, which for the most part is straight up hill from the lowest point to the highest point of the race entirely exposed to the sun. This was the part where I let go of my heart rate limits (more on that below) and went for it. I felt strong from 25 to the aid station at mile 27 but the last 4 miles seemed harder than the first 27 combined.

Coach Ian Cruz, Big Chief 50K Ultramarathon
Big Chief 50K finish line

Strategy and reasoning behind it:

Dealing with elevation (monitoring heart rate):

I likely wasn’t adapted to the elevation for the run. One day trip to run an 11 mile training run isn’t enough. I had some wishful thinking that some of the breath-restriction methods I mentioned here (as noted in the books Breath: The New Science of a Lost Art and The Oxygen Advantage) would help, but of course it’s different actually being in elevation.

Unsure of how my body would acclimate, I just tried to keep my heart rate below 152bpm for the first 25 miles of the Big Chief 50K, before letting go of all rules and just trying to get to the finish. Staying below 152 keeps me in an aerobic state and prevents me from constantly fueling.

I personally don’t believe Zone 4 (152bpm-171bpm) is great for long-term health, even though it’s the zone where you get that “runner’s high”. I only run at Zone 4 for half-marathons, but never marathon or ultramarathons. 

That being said, my heart rate was higher than I would have predicted in elevation, given my perceived running effort and pacing. Not only that, it seemed extremely sensitive and moved really quickly in both directions. I could go from 135bpm to 180bpm without much difference in pace, notice it, slow down and see it drop back down to 135bpm in 10-15 seconds. That truly makes me wonder if the data on my Garmin Watch is accurate, or how much of a lag there is on the data displayed.

Despite my skepticism of some of the high readings, I respected my Garmin Watch and slowed down as necessary. This lead to much slower jogging or power walking to get my HR back into the zone I wanted it to.

Monitoring glucose levels (Race Fueling):

Simultaneously, I was monitoring my glucose levels. If my heart rate was to spike and stay elevated for a period of time, I would expect my body to break down glucose and my blood sugar levels to rise. However, that never happened and my blood sugar levels stayed between 90-100 the entire race, even when my heart rate temporarily spiked to 190!

With real-time data from my CGM, I didn’t have to follow any rule to fuel every X number of miles. My race was mainly aerobic with an average heart rate of 148bpm and stable glucose levels. As a result, I only fueled twice with glucose: once at mile 11 before an uphill climb and again at mile 23, knowing the toughest climb was coming up at mile 25.

  • I used UCAN superstarch as a slow-burning carb to avoid any blood sugar crash.
  • At mile 16 or so, I also took about 5g of HVMN’s ketone esters which are an exogenous ketone source. This is an alternate source of energy (ketones are the byproduct of fat metabolism). Typically, the presence of insulin stops fat metabolism, so people don’t fuel off of carbs and ketones at the same time. HVMN’s ketone esters supposedly allow you to carb load and also be able to fuel off of ketones.

I was happy with the stable source of energy throughout the race. Note that many athletes fuel with fast carb sources such as gels and, literally junk food – snickers, M&M’s, etc. When fueling this way, athletes get blood sugar spikes above 160 and crashes below 60, which leads to bonking! This puts athletes on the blood sugar rollercoaster, with several crashes throughout the race. Not to mention this is absolutely terrible for long term health.

An interesting note from Phil Southerland (Supersapiens founder) is that fueling with carbs prior to a race leads to a pretty significant blood sugar crash. He found that the ideal time to fuel is at least 8 minutes into your workout.

I’m part of the Supersapiens Athletes Facebook group, and many athletes post their data showing those drastic spikes and crashes. See below for a comparison of my glucose levels during my race to another cyclist who fuels with carbs. I find this so shocking!

Levels Health CGM during Big Chief 50K
My glucose levels during the Big Chief 50K

Glucose levels of a glucose-dependent athlete

Athletes like Eliud Kipchoge are using glucose monitors to help understand their bodies and prepare for races. I’ve been trying to see if there are any top athletes who publish their data, with no luck so far. It seems like a lot of trial and error so far.

Dealing with heat (hydration):

Anyone who knows me sees me show up to training runs with no water or fuel. I just show up and run – ready for whatever course our group throws at us.

The truth is I don’t really think training runs need much over-preparation and find it more enjoyable to not stress about anything. If it’s hot I’ll bring water, but as long as my run is a reasonable distance (~10 miles) and it’s not a hot day, I pre-hydrate heavily and have water in my car for afterwards, which seems to be all I need. Running with a hand water bottle, a water bottle on my hip, or even a hydration pack is unenjoyable to me. I also don’t stress over reading elevation charts or strategizing training runs – it’s a training run after all! Training runs are where you can experiment, make mistakes, and learn about your overall level of fitness. The overall theme for this line of reasoning is to keep running from seeming like a chore.

Race days are different. I knew the elevation map pretty well, was aware of my limitations in elevation, and prepared to hydrate heavily in elevation, as elevation alone leads to water loss and it was already going to be a very hot day. The general rule is that your pee should be clear the morning of the race. Check.

I brought along a number of FITAID, RECOVERYAID, and Biosteel supplements to add into my water.  Biosteel and Nuun are my favorite no-sugar (Nuun has very little) hydration sources.

I also didn’t fill my hydration pack prior to the race. The first aid station is at mile 3, so I figured I would avoid the extra weight for the first uphill climb (during a time when it was cool anyway) and fill it there.

Pre-race: Training and Fueling

Training miles:

I’m not your typical ultra-runner, running a low 30 miles a week. I once had ideas that I would try to run 50+ miles per week, since it seemed that was what was required to improve my times – and, yes, I would have to dramatically increase my mileage if I were to become an elite ultrarunner.

But it’s important to remember your why and set your goals based on what’s right for you and not just follow the crowd. For me, running is a thing I do, but it’s not the only thing I do. And to be honest, I’ve felt rather burnt out in other areas of life and don’t want to make running an added stressor.

I’m proud that I’ve run every single day this year, running only 5K/day and then hitting long runs (10-20 miles) every Saturday. I’m not really willing to give up anything else (boxing, work, sleep) in my life to squeeze in the extra mileage. Being able to run an ultra is a bonus – not a priority.

Fueling (Night-Before):

Yep, I carbo-loaded. Although I don’t go crazy fueling during my race, I did carbo-load the night before. It’s definitely beneficial to have increased glycogen storage for your race.

My carbo-loading is literally just the night before, not 3 or 6 days prior to a race like others do. I stay relatively low-carb the entire week before my final dinner being a carbo-loading meal. If I were to carb-load 6 days in a row, I’d probably gain 10-15lbs before the race. Runners World suggests I should eat 2,400 calories of carbs per day as a carbo-load – that is terrible advice, not just for racing but for overall health.

That being said, the night before I let all rules go. I ordered some Pad Thai from Thai Delicacy. One of my prior marathon PR’s was off of Pad Thai, and it may just become a pre-race trend..

Day-Of Fueling:

Ample Meal: I started off my day with my loaded Ample Meal smoothie – the same one I used for the Antelope Canyon 55K. My smoothie is made of the following:

  • Ample Meal + Chia Seeds, Hemp Seeds, Bitter Melon Extract, Beta Alanine, Essential Amino Acids, Cordyceps Mushroom, and UCAN Superstarch (approx 800 calories/drink, or 3,200 total calories)
  • The Ample base is 600 calories and is loaded with healthy monounsaturated fats (coconut, macadamia, sunflower, chia), while restricting inflammatory omega 6’s, organic greens (wheatgrass, barley, chlorella), protein (grass fed whey, egg whites, pea), fiber (tapioca, acacia, chicory), and probiotics.
  • $30 discount here

Gen UCAN: I use UCAN as my slow-burning source of carbs that does not spike and crash blood sugar.

  • Use code UCANREFHNP4YHJXR6 for $25 off
Abstaining from coffee/music/etc.:

While the taper includes reducing mileage to allow for physical restoration, I also take it as a time to restore parasympathetic (“rest and digest”) balance. In addition to the physical pains I may feel from training, chances are that I may also be in an overtrained state, with my sympathetic (“fight or flight”) system in overdrive.

I detox from coffee and caffeine and I meditate. I focus on my breathwork. And I spend more time listening to audiobooks or podcasts instead of playing out the music I’ll be listening to during the race. Most trail runners don’t even listen to music while running, but I do for races only.

Post-race thoughts:

The Big Chief 50K was a challenging course that provided such an insight into my own body. Naturally, I went down the rabbit hole of researching the topics noted above and listening to podcasts.

I highlighted three CGM companies: Levels, Supersapiens, and January in the past and use the Levels Health app myself. Levels put out the Ultimate Guide to Healthy Blood Sugar Ranges, which guided the way I approach my blood sugar. But after the race, I was frustrated. How do I actually achieve a PR within that narrow range of glucose levels between 90-110? 

So I listened to Phil Southerland, the founder of Supersapiens. Phil is a type 1 diabetic who founded the first all diabetic pro cycling team, Team Nordisk. Supersapiens seems to have more of a focus on athletic performance than longevity. So I was shocked when I heard him say that many athletes have a target glucose range of above 160.

There was also a study of ultramarathon runners wearing CGMs, and the data showed better results with even higher glucose levels, with them peaking as high as 240. I’m not sure what to make of the results, as it was done with a small sample size of 7 participants.

Application of Continuous Glucose Monitoring for Assessment of Individual Carbohydrate Requirement during Ultramarathon Race

I reached out to Josh Clemente afterwards, and he made a great point that optimal performance doesn’t equal optimal health. Peter Attia’s take on Zone 2 training is next up on my list. I can’t say I have hard solutions to how I will fuel going forward – I’m still learning and developing my philosophy. But my general strategy will be to do my long runs in Zone 2 with stable glucose levels. I’ll be strategic on when to push it and do speed work (800m repeats, etc.) separately.

Being fitter does not equal being healthier. Sure, the person who can run a half-marathon will be healthier than the person who never works out. But that relationship is not linear and does not extend to the extremes. Everybody has their own preference as to how much they choose to sacrifice their long-term health in the name of their performance goals.

I struggle with that balance often, but am leaning towards focusing on my health.

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