Running frequency chart

We recently added a new chart on the Trends page showing how many days per week you’ve been running, on a rolling 7-day basis. Let’s dive into the science behind it and how it’s implemented in myTF.

Why track frequency (running days per week) separately from mileage? Because the same 40 km week is a different stimulus spread across 6 short runs than packed into 3, and because changing frequency is a load change in its own right. Going from 4 to 6 runs a week compresses your recovery windows even if total distance stays flat.

The science of running frequency

Nielsen’s 2012 systematic review on training errors and running related injuries analysed studies on running frequency, and most pointed the same way: higher weekly frequency linked to more injuries, and 6 to 7 running days a week carrying the highest risk. The main exception was a study in the British Journal of Sports Medicine (Taunton et al., 2003) which found that once-a-week runners, women especially, also got hurt more, which hints at a U-shape rather than a straight line. This could be explained by the fact that running once a week may not be enough stimulus for the body to adapt to running, especially if that single run’s distance ramps up over weeks.

The catch is that frequency is tangled up with mileage, since people who run more often usually run more overall, so it can be hard to pin down how much is due to frequency itself.

Running frequency in myTF

Run frequency is plotted as a chart in the Trends page. myTF counts running days, not individual activities. If you log your warm-up, workout and cool-down separately, that still counts as one day.

The zones are cautious on purpose:

• 1 running day a week is blue: some studies have found higher injury rates in once-a-week runners, possibly because each run becomes a relative shock to tissues that haven’t been loaded recently.
• 2 to 5 days is green: that’s where most recreational runners sit.
• 6 to 7 days is orange: running that often leaves little recovery between sessions, and it’s the band the research links to the highest injury risk, though that’s hard to untangle from the extra mileage that usually comes with it.

The modest quality of the underlying sports studies means there’s no red zone, and why frequency reads best alongside your other metrics rather than on its own.

References

Nielsen RO, Buist I, Sørensen H, Lind M, Rasmussen S, 2012. Training errors and running related injuries: a systematic review. International Journal of Sports Physical Therapy. 7(1):58. Available at https://pmc.ncbi.nlm.nih.gov/articles/PMC3290924/

Taunton JE, Ryan MB, Clement DB, McKenzie DC, Lloyd-Smith DR, Zumbo BD, 2003. A prospective study of running injuries: the Vancouver Sun Run “In Training” clinics. British Journal of Sports Medicine. 37(3):239-44, DOI: 10.1136/bjsm.37.3.239