Lost a ton of fitness after a 2 week hiatus. Is this even possible?

A couple of thoughts. First run back after 2 weeks off is always a little different, at least for me. I might be well rested but it feels off and kind of awkward. It might also be a bit psychological. You're worried about whether you lost fitness so are uber-aware of any difficulty at all. Marathon pace isn't easy. It shouldn't feel like an easy pace. Make sure that you're not psyching yourself out.

You'll get the fitness back soon enough. Just don't try to run MP on your first few weeks back. Go easy.

The first run after taking several days off is going to be rough. Just run easy for a week and ease back into it.

As a rule of thumb, you can take about a week off without losing much fitness. Thereafter, it will take about twice the time you were off to get back to where you were before you took time off, i.e., two weeks off means about four weeks to get back to where you were.

For older runners over 60, if you take more than two weeks off, it will take months to get back to where you were. You might never get back. That's why avoiding injuries should be the #1 priority of older runners.

Interesting observations about fitness. A) What makes 1 week off OK, but each week after that so damaging to fitness? B) What's the minimal "maintenance" mileage you reckon for someone who usually runs 50mpw? C) Any source on this theory?

fisky wrote:

The first run after taking several days off is going to be rough. Just run easy for a week and ease back into it.

As a rule of thumb, you can take about a week off without losing much fitness. Thereafter, it will take about twice the time you were off to get back to where you were before you took time off, i.e., two weeks off means about four weeks to get back to where you were.

For older runners over 60, if you take more than two weeks off, it will take months to get back to where you were. You might never get back. That's why avoiding injuries should be the #1 priority of older runners.

It's just anecdotal and personal experience. I've seen it in other runners. I've wondered if it has to do with mitochondrial aging or micro scar tissue formation during the downtime.

I've been forced to take 4-6 weeks off due to injury after age 60 and in spite of staying injury free for months afterward, I never returned to my previous level of fitness. As a result, I am EXTREMELY cautious in avoiding injury. I quit about 1 out of every 10 workouts due to a minor pain that I fear might become major if I kept running. It has allowed me to remain a top AG runner in my events.

I don't think you have to run, however, to maintain fitness. If you can spin, water jog, or do elliptical on a machine that mimics the running motion, that would probably help.

As far as the OP is concerned, this doesn't apply for runners who aren't approaching senior citizen status.

run easy for 2 weeks. Add some strides. You'll be back at it in a month. You WON'T be back at peak fitness. But, you'll be back in training shape.

I'm weird, but I usually feel great on my first run back after a 2-3 week break (I usually just go easy for about 5 miles and stretch a lot). However, I typically notice that my 2nd day of running is the one where I feel sorta like crap, and first 'hard' session feels like crap. In general, if I take 2-3 weeks off over the holidays (typical for me) it seems to take another 2-4 weeks of running to return to my old level of fitness. FYI: I'm 48 years old running anywhere between 35-50 mpw. When I was young, I think I recovered from 2-3 weeks off in like 2-3 days!

oheo wrote:

run easy for 2 weeks. Add some strides. You'll be back at it in a month. You WON'T be back at peak fitness. But, you'll be back in training shape.

This. Really, with a couple easy days and some strides you might be feeling quite good again in a week. But either way, it won't take long.

I have read a number of studies that show aerobic fitness starts falling at about a week, muscular strength starts falling at around 4 to 5 days, and coordination (for whatever skill you practice, and yes, running fast would fall under this) starts dropping within about a week as well.

If it is only a week or two that you're off, they come back about just as fast. But as fisky noted, if you are older and you take a longer amount of time off, it can take a really long time to come back. And some things don't come back.

After two weeks off 6:50 isn't your MP any more.

3 is definitely possible as you reacclimatize in general, but what you're describing is probably a function of items 1 and 2. After 5-7 days of no running, a person begins losing blood volume, mitochondrial density, and VO2 max (the two former would be what are likely affecting you). This means that both muscle oxygenation and energy supply are decreased and aerobic fitness is lost as a consequence. Overly cold weather also inhibits performance before your body adapts to it.

If I were you, rather than coming back and immediately running race pace (which makes it easy to notice loss of fitness and can be demoralizing), I would ease back into things. Do a week or two of easy mileage, maybe tossing in a longer run if you're feeling good, and then begin incorporating non-strenuous workouts like CV and tempo. How you proceed from there will depend on what race distance you're training for. Best of luck getting after it.

It seems commonly understood that 10 days off after being fit and having consistent training will only result in a 90-95% loss of fitness. This is because the workout you do today will not be "added" to your fitness for 10-11 days from now. That's why a 10-11 day taper is used.

Always look at training from a 10.5 and 21 day (10.5 x 2) perspective. "Did i miss training 11 days ago that might affect me today?" or "This weekend of bad diet and no sleep might be felt in 11 days."

Like many said, this number becomes bigger as you get older. As a 36-year old, I can attest that it takes longer to get back into shape now than it did 5 years ago.

tfrrsftw wrote:

After 5-7 days of no running, a person begins losing blood volume, mitochondrial density, and VO2 max (the two former would be what are likely affecting you). .

I'd agree on loss of blood volume, but not mitochondrial density. As a rule, structural elements (capillary density, mitochondrial density, left ventricular hypertrophy) are a lot more resistant to detraining than metabolic and enzymatic changes. mitochondrial CAPACITY, for sure can start decreasing within a wee due to decreased aerobic enzyme kinetics / concentration, but that can be reversed relatively quickly due to years of training and maintained mitochondrial capacity

OP, you've likely lost some of the more transient training effects, but be confident that your long-term adaptations will not go away in as short as 2 weeks.

Your body is probably just rusty/sluggish. It always takes me a few runs to get back into the rhythm after a hiatus. Your body is likely not used to feeling this fresh and your running muscles haven't been activated in a while.

I did the same thing this summer. The first two runs were so slow and difficult compared to only two weeks before. I think it's simply just getting back into the groove, so to speak. Within a week I was back to my normal time. I think I probably increased my fitness by taking the time off, too. Now I'm running incredible time and it's like 38F everyday here.

1. Atrophy of everything related to running. It happens quickly after 1 week.

2. I find that two 5 miles runs a week will keep atrophy at bay and will even increase fitness and prevent injury. Plus you stay fresh.

3. My own observations over many years.

1 week off gives often an increase in fitness, due to the tapering effect.

After 2 weeks you really start losing fitness fast.

Recently I had to take 4 weeks off due to a calf strain. I restarted with short easy runs for a few weeks. I’ m now at this point and what feels like treshold pace now is 40 sec/mile slower than what felt like treshold pace before the injury.

fuyki wrote:

1. Atrophy of everything related to running. It happens quickly after 1 week.

2. I find that two 5 miles runs a week will keep atrophy at bay and will even increase fitness and prevent injury. Plus you stay fresh.

3. My own observations over many years.

I completely agree, especially with a few 20-30 second pickups now and then around 5:00 pace. I run two 5-mile runs a week at around 6:45-7:45 pace as well and play some other sports (soccer, tennis) and am probably still in 17:30 5k shape. Have been doing this for a couple of years in my 30's after I decided training every day wasn't helping my life much. 10 miles a week. I also time trial a mile every year on my birthday.

You definitely stay bouncy and fresh only running twice a week, but have energy for everything else you want to do.

fisky wrote:

The first run after taking several days off is going to be rough. Just run easy for a week and ease back into it.

As a rule of thumb, you can take about a week off without losing much fitness. Thereafter, it will take about twice the time you were off to get back to where you were before you took time off, i.e., two weeks off means about four weeks to get back to where you were.

For older runners over 60, if you take more than two weeks off, it will take months to get back to where you were. You might never get back. That's why avoiding injuries should be the #1 priority of older runners.

That 2-to-1 ratio seems like an exaggeration to me. I could barely walk for 10 weeks with a severe group strain. After that, I spent two weeks shuffling on a treadmill and then three weeks building up to my previous mileage. Immediately after that I ran the fastest 5K (of 6) I've run this year.

- over 50

Groin strain.