Garmin's Sleep Coach Helped Me Run My First Marathon and Beat My Goal Time

I have always had a casual relationship with distance running. In high school, I was on the cross country team and put in quite a few miles every fall, mostly to stay in shape for basketball. At that level, the race distance maxes out at 3.1 miles, compared to the 26.2-mile marathon distance. 

After high school, I would run periodically with several-week bursts where I told myself, "I should run a marathon!" before falling off the wagon for any number of reasons. I did that for years before deciding on Jan. 1, 2024, that I was finally going to do it for real. Before that day, the longest run I had ever done was 8 miles, a far cry from the distance I would have to go to complete my first marathon. I only ran 50 miles in 2023, so I needed a lot of training.

The key to marathon training is being able to run (almost) daily, and to run every day, you need to have excellent recovery. That starts with sleep. I used the sleep tracking and sleep coaching features on my Garmin Forerunner 965 to maximize my recovery, be more strategic about my training schedule and be as ready as possible on race day. 

Garmin's sleep-tracking tools and training

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I have worn a Garmin watch for a long time, but it was pretty outdated by the time I upgraded to the Forerunner 965. The new Forerunner has a ton of new features I was able to explore, but the biggest thing I noticed was the sleep features. On my old watch, I didn't find the sleep tracking to be valuable enough to actually wear it on a nightly basis because it really only tracked my sleep duration and sleep stages. 

The Forerunner 965, and most newer Garmin watches, not only tracks your sleep duration and stages, but it also tracks how often you move at night, your nightly stress, heart rate variability and respiration. The device will then synthesize all the factors into a nightly "sleep score" that is provided in a handy "morning report." 

Your sleep score is a huge contributor to another important metric provided by Garmin called "training readiness." Training readiness considers how much and how hard you have been training and how well you are recovering, and then tells you how effective training that day is likely to be. If you got poor sleep the night after a long, challenging training run, then the training readiness score will be low. 

Now, this might sound like a bunch of random numbers that just make things more complicated or are only for the most serious runners -- but I found that these scores directly correlated to how well my training run went that day. 

Read more: I Finally Found a Sleeper Tracker That Records My Naps and Runs.

For example, with a few weeks to go before the race, my training plan called for a 20-miler to really get my body and mind used to running that distance. My sleep score the night before the run was 95, one of my highest scores ever, and my training readiness was also in the 90's. And I was able to complete the distance at my intended race pace. It just felt good, too.

Screenshot by Owen Poole/CNET

On the other hand, I took a trip to Los Angeles in early June of 2024 and got worse sleep than I normally do at home. Before the trip, I expected to feel amazing going on runs along the Venice Beach Boardwalk and near the Santa Monica Pier because of the excellent weather and lower elevation (I live in Reno, Nevada, which is roughly 4,500 feet in elevation, and where it is often cold and windy), but I felt sluggish, and my heart rate was higher than usual for the pace I was running. 

Screenshot by Owen Poole/CNET

There were many examples of this, but the bottom line for me was good sleep equals good training, and bad sleep equals bad training.

There is also the Garmin Sleep Coach feature, which offers advice on how to improve your sleep and recommends how many hours of sleep you should get each night. In my experience, 95% of the time, it recommended eight hours, but if I had a particularly challenging training day or poor sleep the night before, it would recommend eight-and-a-half or nine hours to catch up. Conversely, if there was a day where I had a good nap, the Sleep Coach would say I only really needed seven-and-a-half hours of sleep. 

What affected my sleep scores?

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Fortunately for me, I didn't need to make a lot of changes to my sleeping patterns to accommodate my marathon training -- but I did start to notice behaviors that had negative or positive impacts on my sleep scores and my training. 

This might sound obvious, but if I drank any alcohol, my sleep score would be significantly lower. My lowest score since I started wearing the watch was a 35 out of 100, and it was after a night out at a bar. I already didn't drink often, but I cut out alcohol almost completely so I could train better. 

I also found that reading for 20 to 30 minutes right before bed helped improve my sleep scores. The Garmin Sleep Coach recommends certain behaviors like meditation or breathing exercises to help you destress before bed. I have never been able to meditate, but I think that reading has the same calming effect on my body and mind. 

Also, there was a several-week window during the summer when my house did not have working air conditioning, and the temperatures inside reached 88 degrees most days. My sleep quality took a huge hit in that heat, despite sleeping on one of the best cooling mattresses on the market, and my training suffered, too. 

The biggest thing, though, was just getting to bed and waking up at roughly the same times every day and getting a full eight hours. I noticed that even if I didn't get a full eight hours on one night, I could still be ready to train the next day, but if I didn't get eight hours for several days in a row, then I started to feel the consequences.

How I adapted my training plan

Just because there would be days where I woke up with a low training readiness and sleep score, that didn't mean I would skip running that day. A huge part of marathon training is having the mental fortitude to run on days where you don't feel physically up for it. 

But with the knowledge provided by the Garmin sleep tracking tools, if I had a very difficult run scheduled that day, I could easily swap the difficult run for an easier one I had scheduled for the day after. This helped keep my spirits high, because feeling sluggish or slow on challenging training days makes me feel like I'm not making progress. Also, I managed to do several months of training and hundreds of miles of running (732 miles, to be exact) without any significant injuries, and I think adapting my schedule based on my sleep played a role in that. 

Race-day experience

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I chose to run the San Francisco Marathon because it was the closest full marathon to where I live. The race also happened to be on my birthday, so it felt meant to be.

I had to catch the shuttle to reach the start line at 4:15 a.m., and the race itself started at 5:15 a.m. I actually managed to get a decent sleep score the night before (71), but I did not come close to getting a full eight hours. Thankfully, I had enough adrenaline to get me to the start line. 

I trained to be able to finish the race within 4 hours, which is a popular benchmark for amateur runners and is about 30 minutes faster than the global average finish time. 

The San Francisco Marathon course is very unforgiving. The city is known for its hills, and the race doesn't avoid them. Over the 26.2-mile course, there is a total of 1,700 feet of elevation gain, which is much more than the Boston or New York marathons. 

During the marathon, I ran by the Golden Gate Bridge. 

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The first eight miles felt great and I intentionally had to slow my pace to not overdo it early on. I am extra glad I did that, because the first big hill happened around mile 9, which led up to the Golden Gate Bridge. The hill was very steep but getting to run across the bridge with hundreds of other racers was a truly unique experience. 

The hill to get back to the north side of the bridge was even steeper, and I struggled to keep up with the group of pacers -- but once I got back across the bridge, I was halfway through the race. 

The back half was much more difficult, despite having fewer steep hills. The adrenaline had mostly worn off, and I could really start to feel the fatigue and lack of sleep taking its toll. 

Once I hit mile 20, I was officially in completely uncharted territory, but I was able to keep hitting my intended mile splits, just barely. This section of the course went through the city itself, and I got a bit of a boost of energy from the crowds of cheering spectators.

With less than a mile to go I nearly tripped over a crack in the sidewalk and I slammed my toes against the concrete. It was super painful, and I thought my toenail had fallen off (turns out it was a blister that popped), but I managed to power through and cross the finish line with a final time of 3:58:24, just under my goal time.

Screenshot by Owen Poole/CNET

 I was the 1,580th finisher out of 5,694 runners and finished in the top 25 percent of the men's 30-to-34 age bracket, which felt amazing for my first race on such a difficult course. 

Post-race recovery

After confirming at the medical tent that my big toe was fine, I gingerly walked back to the train station to head back to my AirBnB. I enjoyed a victory beer and a victory pizza (yes, a whole one), and by the late afternoon, I was, predictably, completely wiped out. 

I got into bed around 9:30 p.m., and, according to my Garmin, I didn't fall asleep until 9:56 p.m. I didn't have the energy to do any of my regular bedtime routines. While I slept almost 10 hours, my sleep score was only 65 due to my overnight stress level.

Screenshot by Owen Poole/CNET

This is probably because my body went through a lot, and according to my stress chart, the first half of my night's sleep was high stress, and my stress level lowered drastically throughout the night. The next night my sleep score and nighttime stress level was back to normal though.

Final thoughts

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I think it is really easy to focus on all kinds of different recovery methods like stretching, yoga, foam rolling and supplements for running or any other athletic endeavor -- and while those things can be important and helpful, good sleep really is the key to recovery. Would I have been able to meet my marathon goals without the sleep-tracking tools? Probably so, but I am also glad I didn't have to find out. I found sleep tracking to be incredibly valuable, and I felt like my training really took off once I switched to the new Garmin Forerunner 965 with the updated sleep tracking/coaching tools. 

It was less that having my sleep score and training readiness score meant that I was shifting my schedule around all time. I did do some of that and it was valuable, but it was more about making lifestyle changes to get better sleep so I could maximize my training runs because of how strong the correlation was. 

If you are training for a marathon or a triathlon or you are trying to get serious about your gym routine, I think a sleep tracker of some kind would be very useful. These sleep-tracking features are available on most of the newer Garmin watches, including the affordable Forerunner 165. 

For me, I will be continuing to wear my Garmin nightly as I train for future races.