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What Exertion Looks Like Running the Boston Marathon

By Allison Lynch

What Exertion Looks Like Running the Boston Marathon

On Monday April 15th, 2019, Caroline Shannon crossed the Boston Marathon finish line with an official time of 3:01:56 (6:57/mile), a personal best out of the four marathons she’s run. Shannon, a professional architect and WHOOP member, credits tapering and getting more sleep for a perfectly executed race. “I felt more prepared than ever with my training,” she said.

On top of her three-minute PR, this was Shannon’s first year running a marathon with WHOOP by her side. We decided to take a closer look at her data before, during, and afterwards to see how prepared her body was and how her exertion progressed along the course.

Pre-race Stats:

Recovery: 93%Sleep Performance: 68% (only 5:15 hours of sleep)

Shannon cut her mileage by 50% in the two weeks leading up to the race. The effects of tapering are scientifically proven to increase VO2 max and your anaerobic threshold, which prepare your body for high-intensity periods. While she blames nervous energy for losing sleep the night before the race, she took a long nap the previous day and had been getting to bed much earlier than usual in preparation. Her body still woke up almost fully recovered, as shown by her WHOOP data.

The Marathon:

Below is a map of the Boston marathon course, which begins in the humble suburban town of Hopkinton and travels through Middlesex County until it reaches Boston. We’ve chosen several timestamps along the course to depict Shannon’s WHOOP strain and total calories burned.

The strain (cardiovascular exertion on a scale of 0-21) of Boston Marathon runner Caroline Shannon over the course of the race.

Shannon took off just after 10 am when her WHOOP strain was 7.6. It didn’t take long for that to double; seven miles in it was approaching 15. By the time she reached Wellesley College, otherwise known as the “scream tunnel” for the crowds of cheering women, her strain had hit 18.2 and she was averaging a 170 bpm heart rate. Next up, of course, were the Newton Hills. For anyone who has run Boston, the Newton Hills will make or break you. You either power through patiently, albeit uncomfortably, or you slow down significantly and accept that your quads and glutes will be on fire for the next six miles.

It was at this point that Shannon’s strain breached the 20.0 mark. WHOOP strain operates on a proprietary 0 to 21 scale; the closer you get the 21, the harder it becomes. Shannon’s incremental increase in strain as the race progressed was basically her max effort as she approached 21.

Post-race stats:

Overall Place: 2900Gender Place: 201Division (age 33): 176Final time: 3:01:56

Total Day Strain: 20.7Recovery the Next Morning: 37%HRV: 16 (down from 36 the day before)

Following the race, Shannon was elated to find out she had PR’d by three minutes. She had done everything right, and thankfully the weather this year was nothing like the harsh wind and stinging rain of 2018.

Congrats to Caroline Shannon and all the Boston Marathon finishers this year. WHOOP is proud to support a strong city of runners and be a part of the running community.