20th Denver Colfax Marathon 2026

On May 17, 2026, I ran the 20th Denver Colfax Marathon. The full race FPV/POV video can be viewed on YouTube here:

I trained for this race by following a Garmin Coach plan. The plan was setup the week after the Atlanta Marathon. The plan included the St. Louis Marathon along the way. There will be a separate video with further details of the plan.

This was my first marathon where the altitude is a mile high. I did not know what to expect with the elevation change. My Apple watch gave quite a few warning of vitals being out of normal ranges and indicating that it could be caused by recent travel to higher elevation.

Also, after arriving in Denver, I started getting a runny nose. I don’t know if I am allergic to something in the area or got sick along the way. The runny nose would disappear and return periodically. The first night I had difficulty sleeping due to the blockage in my nose. But it got better subsequent nights. I still had a tough time sleeping though - but that seems to happen for all my travels.

I decided to purchase CityPASS again for Denver. The day before the race I probably walked too much visiting tourist attractions like the Denver Aquarium and Denver Art Museum. In fact, by the time I got back to my hotel room, I developed a pain that appeared to be my glute area. I spent the evening trying to massage the area and identify the problem spot. I think I was able to fix it since there was no pain in morning.

Sadly, my Outdoor Research Cathode jacket that I’ve had since 2016 got a hole in a pocket. So need to find if I can fix that. They don’t make that jacket anymore and don’t seem to have a similar replacement model either.

Travel

I flew from BWI to DEN direct via Southwest Airlines on May 15. To get into the city, I rode the RTD “A” Train which cost $10 and took about 50 minutes to get to Union Station in the city. I was confused about the system. I saw the terminal to do tap-to-pay and got the confirmation but nothing showed up on my phone. Being from the DC area, I am accustomed to having a trip started notification when entering the metro system. But it worked out since the following morning, I got a notification on my phone for $10 RTD transaction.

I stayed at Hyatt Centric Downtown Denver for three nights. I booked it as it was one of the official partner hotels for the Denver Marathon. The official partner hotels have a free shuttle bus to the start of the race. Since the race started early at 6:00am, I did not feel like having to figure out a way to get to start on my own. One issue is when I first left my room to get dinner, the door would not lock. Eventually somebody called since I was evidently trying too much trying to close and lock the door. They swapped me to a different room since the maintenance person could not fix the door. I ended up with a room with two queen beds instead of single King bed and moved up several floors, no view improvement this part of the city. Also a higher floor means it takes longer to enter the room and leave the hotel. The rooms have a “cooler” instead of a refrigerator so I was not able to store groceries like I have been accustomed to. I did buy some berries and broccoli that I thought would survive for the three days for convenient healthy food.

To return home, I boarded the Free MetroRide to Denver Union Station where I boarded the “A” Train back to Denver Airport. On my train, a person came by to check tickets. I was curious how they would check mine since I did tap-to-pay, but all I had to do was activate my apple pay card and tap it on their device and it detected a ticket. The Denver airport has an East and West security checkpoint. I tried to select the shorter line but it probably doesn’t matter since it takes a few minutes to even travel between the checkpoints.

My flight back to BWI was delayed by about 3 hours. I arrived at BWI at about 11:00pm instead of advertised 7:30pm. I think due to the excess delay, I can get reimbursed for some excess expenses incurred due to the delay. For example, I normally take public transit to/from the airport. Due to the late arrival, the public transit buses stopped running so I had to pay an extra ~$60 to take ride share home. So I plan to submit for reimbursement.

Expo

The expo was held at Empower Field At Mile High. To get to the expo, I took a bus from my hotel and then walked on some trail path to the stadium. I got somewhat lost along the way because I decided to follow a person ahead of me. But it turned out they and a bunch of other people that later appeared behind me were going to a different place so I had to double back and get back onto the right path. It worked out since I arrived as the doors opened to let people in.

There was a single entrance for all participants which later separated by the events. The first stop was bib pickup, then there was the store and sponsor tables. I picked up my double marathon prize at the store. Eventually walked through several sections of vendors and sponsors and eventually picked up shirt. At the end, outside, there was a Hyundai SUV with all the marathon participants names printed on wrapping on the car.

Carb Loading

Since the race was Sunday, I started eating extra Thursday morning. I decided to count the amount of carbs consumed each day again:
Thursday: +275g
Friday: +368g
Saturday: +491g
These were a minimum based on available nutrition labels and estimates. The numbers for Thursday and Friday are low because a lot of stuff I did not bother estimating. But I felt I hit my target carb count.

Race Day

On morning of the race, I exited the hotel and boarded the shuttle bus at around 4:15am. As promised, buses left promptly at 4:30am. The buses took a roundabout way to get to City Park which took about 30 minutes. They first went North which was kind of scary since East would be the expected direction but due to city traffic, much faster to go around.

The buses remained onsite until about 6:00am so people could stay aboard until then. Convenient for Half-Marathoners with a 6:30am start time instead of 6:00am for Marathon. But it was a little walk to get to the actual race area. I left to drop a bag at gear check and then wander the corrals for photo opportunities.

Weather

The weather was nice at start and warmed up at finish time. It was a partly cloudy day with the sun popping out now and again.
At start around 5:55am, the temp was 54F with 41F dew point.
At around 11:00am, the temp was 65F with 37F dew point.
At times when the sun was out, it was feeling hot with sections without shade.

Extra Stuff

As per usual, I was wearing my recording gear:

• GoPro Hero13 Black with Headstrap 2.0 and Contacto
• Anker Portable Charger

Nutrition

Before the race started, I ate about a cup of crispy rice serial which provided about 30g of carbs.

Carry:

• 1x Bonk Breaker Green Apple Energy Chews
• 3x Sport Beans(R) Jelly Beans Assorted Flavors
• 8x Mott’s(R) Assorted Fruit Flavored Snacks
• LMNT (mixed with water in 550mL bottle)

With the experience from St. Louis Marathon, I decided to do a 50% increase of carb intake per hour instead of 100%. So I was targeting about 60g per hour. I think it worked better this time in that I did not experience of having to vomit during the race. But I did encounter the usual feeling of being full and not wanting to eat. I tried to supplement with Gatorade available on the course but often missed the pickups. So something to be further studied and adjusted.

On the course, I skipped the first few water stops but then did start visiting them after mile 14. I was trying to get Gatorade but often I would miss it.

Race

When the race started, I quickly encountered the challenge of running at altitude. My heart rate at the start was about 20bpm higher then usual at start. The race quickly became a test of determination and discipline as I felt like I was already at mile 20+ even though it was only mile 6. I held off from walking until about mile 14 where I started visiting the water stops.

From then on, I would usually do a walk/run approach. I was mainly just counting steps in my head. At first I would run 20-30 steps and then walk 10 steps. But eventually it turned into whatever I felt like at the moment. I tried to take advantage of running the downhill sections without stopping.

Mentally, I was also calculating when I could just start exclusively walking and still meet the course time limit. Of course I did not want to resign myself to walking just because I was lazy and could do so. So i kept trying to run. I just went through the course mile by mile. Some miles were longer than others.

Towards the end of the race, I mentally tried to target a 5:00 time. I initially thought a 4:45 time was out of reach But as the end got nearer, I realized 4:45 was within grasp. In the last mile, I told myself to just hang on and run it in at whatever pace I could manage without stopping. The end section is quite long and winding and I wanted to walk since it seemed to go on forever. Eventually, I saw the finish line. First, I confused the start line with the finish line but realized the finish line was further to the right. At some point I decided to make my move and started sprinting down the stretch. For the first time in many marathons, I did not cramp at the end I was passing people all along the end stretch and slowed down as I crossed the finish line, checking of Colorado.

Some other thoughts:

• I stopped at a potty on the race course which took some time but probably helps to reduce the water weight. It added about 0:43 to my time.
• I repeatedly checked my GoPro to try to make sure it was level on my head. But I guess to no avail since footage still ended up crooked.
• The race course is busy since there is marathon relay and 10 mile race. Since I was just in my own head, I didn’t pay any mind to people passing me.
• After the race, I visited the Denver Museum of Nature and Sciences which was nearby. I remember thinking to myself during the race that I can’t fall apart or push too hard since I need to still be in shape to visit the museum to finish my CityPASS.