The London Marathon is the peak of European marathon’s in the spring. One of the six marathon majors, it brings out the best in elite runners. UK’s very own Phil Sesemann is one of those elite runners that put this race at the focus of his 2023 season. Following an aggressive training block, Phil was able to run a 2:10:23 and secure 8th place overall at the 2023 London Marathon. How did Phil go about running so fast? His training block and data can be viewed below as COROS provides a full analysis of his training leading into race day!
Phil’s watch: COROS Pace 2
Analysis: COROS Training Hub
London 2023 Training
COROS Education: Athletes can view their total volume within the COROS Training Hub
During the 24-weeks leading up to London, Phil was able to log 3979 kilometers while averaging a 4’07” min/km pace! This volume equates to 165.80 km/week during this span of time. When we look at elite runners, there is always one thing they have in common. The ability to continuously put in larger volume weeks to improve on their overall aerobic base! For amateur’s looking into this article, note how Phil averaged a 4’07″min/km pace which is squarely in his aerobic endurance zone. Most of his kilometers were easy, but none-the-less he was able to put forth a huge amount of training leading up to London!
Build in Fitness
COROS Education: Base Fitness allows athletes to see trends in fitness over time.
While Phil’s volume is noteworthy, it should also be stated that he didn’t start his London build until Jan 16th. Allowing his off-season to finish properly, Phil started his build and quickly built his Base Fitness from 108 to 151 at it’s peak. Base Fitness is a 42-day rolling average of your Training Load. Essentially, during the build, Phil was able to train longer and harder as his body become acclimated to the stress. For athletes looking to ensure proper training and a build in fitness, this is the tool/chart you’ll want to keep a close eye on!
Training Intensities
COROS Education: Athletes can see where they spend most of their time training through the Pace Zone Distribution Chart.
When starting out training, athletes want to build base in order to sustain harder, more specific training later. When looking at Phil’s intensity zones, he was able to get 52% of his total training in Zone 1 from 24-weeks out until race day. As we get closer however, you can see Zone 2 (Aerobic Power) start to increase. Many elite athletes will race a marathon in their Aerobic Power zone and therefore, require more specific training at this intensity. By 4-weeks out, Phil had only 23% of his training in Zone 1, 43% in Zone 2, and 18% in Zone 3 (Threshold). The other small portions were higher end efforts to ensure turnover and VO2max were where he wanted them! This is a great example of a progressive build that mirrors the overall affect to his Base Fitness chart.
London Taper
COROS Education: Training Status shows fatigue and how ready an athlete is for peak performance.
With any good training plan, there is always a taper! Many times, athletes are unsure of how to properly taper or when to start. COROS allows athletes to see how their fatigue is trending as they get closer to race day. When you mix your Base Fitness with your Training Status, it provides an overall look at how the two match up. In Phil’s case, another fantastic representation of using data to your advantage! Phil was able to maintain a high Base Fitness after his peak while allowing his overall Training Status (Fatigue) to reduce. Phil raced London with a score of -18 which is firmly in the “Performance” zone based on COROS algorithm’s. One thing to note is that Phil actually ran one hard workout during his taper to help his fitness maintain while he tapered! This is a tactic not often used, but it worked to perfection in Phil’s strategy!
21+km Run One Week Pre-London
COROS Education: Athletes can analyze workouts within the COROS Training Hub.
One of Phil’s last hard workouts came one week prior to race day. Running a half marathon in 1:18:38, Phil was able to obtain 305 Training Load and boost his Base Fitness one last time. By having this run spike fitness, Phil then took the next six days relatively easy to ensure Training Status (fatigue) dropped. During this run, Phil averaged 182 cadence which is just below his race day turnover. Without this run, Phil would have risked having his Training Status too low and ultimately becoming stale. When looking at your COROS data, be sure to keep a close eye on your metrics so you know what is needed at what point. With data, athletes can ultimately dial in their approach weeks in advance!
2023 London Marathon Race
COROS Education: Athlete splits are within the activity analysis window.
When you have a strong training block, you’ll have the confidence to execute on race day. As can be seen from the 5k splits above, Phil was able to hold a steady pace of 3’03”-3’07″/km. This is a display of fantastic pacing and fell right in his Aerobic Power pacing zone. With all of the training Phil put in, along with the specific intensity approach as he neared race day, this was spot on for his current fitness! Not only was Phil able to hold a great pace, but his cadence is also elite! Many amateurs tend to run in the 155-175 range. As seen above, Phil was often in the mid 180’s with his best 5k splits being at 188. For any athlete looking to improve their performance, there is much we can take away from Phil Sesemann’s London Race!
Key Takeaways
As all runners look to improve, there are often questions about how they should go about this! Many times, the answers are in the data. When we look at Phil’s COROS metrics, they provide a solid foundation for anyone looking to improve. Phil built his volume initially with 52% of his training in Zone 1. As race day grew closer, he was able to sustain more training in Zone 2 and 3. By doing this, he was able to not only build his Base Fitness, but also his specific pacing for race day! Finally, he was able to dial in his taper and ensure his Training Status was in his “Performance” zone. If you are looking to improve as an athlete, this is a strong case-study on what a proper marathon build looks like. As you get set to tackle your next race, let COROS be along for the journey. All of the data and software discussed in this article is free for all COROS athletes! So, as you head out the door and explore perfection, be sure to hit start on your watch and let your data guide you to your best performance yet!