Gotta Run: How fast do you lose fitness when you stop running?

Published 12:00 am Saturday, December 3, 2022

Most runners and even some dedicated walkers don’t like to miss a day of doing so. What happens when we take time off and how fast does it take to lose fitness? Sometimes there is an injury that needs to heal or some otherwise important medical reason to stop for a while. Rarely, there is a certain staleness in training where none of the runs are fun and nothing else has worked.

I had my own concerns about missing time earlier in the year when I had a kidney stone and a resulting blood infection that caused a hospital stay and only minor exercise for a month. I began to research how long we can retain our normal fitness level once we stop.

Turns out that the fitness decline starts to happen within just a few days. Runners World posted an article that said, “It only takes a few days to get out of shape. That’s right. Stop running for just a week, and your maximal aerobic capacity (max VO2), one of the key indicators of performance potential, begins to decrease. Take two to three weeks off, and you’ll add a minute or more to your 5K time. Stroke volume, the amount of blood pumped by the heart per beat, also wanes by 10 percent or more in just three weeks. Even your muscles’ aerobic enzymes (key chemicals that help produce the energy you need to run) fall by 25 percent or more in 21 days.”

And here is their suggestion on how to stay in shape while taking a break not associated with injury or medical condition. Don’t stop training but do it on a limited basis and you won’t lose fitness. Dr. Owen Anderson said, “During your break, run just once a week if you ordinarily train three or four times, or twice a week if you usually work out five to seven times. For each session, complete mile repeats at your 5-K pace (the speed at which you would have run the 5-K before your break started). Divide your customary weekly mileage by 10 to determine how many reps to do. For example, if you ran 30 miles per week before your break, do three 1-mile repeats per workout. The mile repeats will almost completely prevent losses in running capacity. In other words, you’ll get a break without losing fitness.”

After years of running almost daily, I felt like I was starting over after my own period of downtime. We’ve worked too hard to give away so much fitness by choice.

I mentioned meteor showers in a previous article. Look for two more chances to see them, the first being across the sky on the night of Tuesday, Dec. 13, into the early hours of Wednesday, Dec. 14, as the Geminid meteor shower peaks at as many as 100 meteors per hour. A bright moon could limit visibility.

The last possibility is on the longest night of the year, Dec. 21, when the Ursid shower seems to come from the Ursa Minor or the Little Dipper. I will be out looking for both!

Our next running event on Dec. 10 is one of the friendliest events of the year, Santa’s Run for Hunger 5K and Fun Run. The Millbridge Ruritans host Santa annually on this day and all proceeds will benefit Rowan Helping Ministries. Held in conjunction with the Holiday Bigfoot Reunion, camping and “meet and greets” are scheduled with the big furry creatures along Kerr Mill Road. A human bigfoot shoe contest will be held following the race with all runners and volunteers eligible by wearing shoes over size 10 for women and 12 for men. A pancake breakfast will be held following the run/walk and all participants can wear jingle bells, presumably to keep from startling any visiting Bigfoots near the camping area.

Look for more information on this and other upcoming events at