You and I both know that I  am not a fitness influencer.

I host a science channel. So I am here with the relatable fitness content; the guidance for the average  person who tries to be a little   healthier by making a resolution  to go to the gym every January… and never makes it through the whole year.

When you, perhaps inevitably, stop exercising, it  can feel like all of that effort was for nothing. Like you lose the gains  that you worked so hard for. But there’s research out there  telling a different story.

Studies suggest that even if  you give up exercising after   only weeks of sticking to your goal,  you keep some of the improvements. You can pick up that good habit  months or even years later and   still benefit from the work you put in before. As it turns out, your burst of motivation can  help you out for longer than you might think. [♪ INTRO] You know exercise is good for you, and so do I.

That’s why every year, around January,   we spend just enough time using that  gym membership to justify keeping it. Many people quit after a matter of weeks. So many that there’s a name for this time  after a New Year when your gym empties out.

It’s called “quitters’ day.” So if you’re thinking about dialing the exercise  back right around now, you’re not alone. Whenever your own personal quitters’ day is,   that’s when you begin the  long process of detraining. This results in your body slowly losing the gains  you made during your temporary training regimen.

And luckily, it doesn’t all happen immediately. In fact, some of those gains stick with you   for long enough that your next  gym attempt is more effective. Now perhaps, you’re watching  this video from a treadmill,   still going strong with  your New Year’s resolution.

But if your resolve is starting to waver,   whatever time you’ve already spent  working on yourself has been worth it. Let’s say you stick it out for  16 weeks of exercise this year. If you start in January, that  would bring you to April.

Maybe you quit at that point  and take the next 10 weeks off. You might think that your resolution  training was all for nothing. You would be wrong.

This exact timeline was tested  in people aged 60 and older. So the resilience that the researchers  found wasn’t just a matter of being young. Study participants started out completing a  circuit of either strength training exercises,   like what you might do at physical therapy,   or moderate cardiovascular exercises, like  biking, for 20 minutes three times per week.

As the study went on, they ramped up the workouts. From all that hard work, participants   improved both their cardiovascular  endurance and their muscle strength. Then, when they stopped,  some of the gains were lost.

Nobody’s surprised by that. It’s when the researchers looked at which  gains stuck around that things got interesting. After weeks of detraining,   the participants didn’t all end up back  at their baseline from before training.

They held onto a significant  amount of cardio fitness. Their recently acquired muscle strength,  on the other hand, went away faster. So over ten weeks, they were  definitely in a period of detraining.

But it didn’t completely demolish their  progress, particularly for the cardio group. In fact, when they started retraining again after   10 weeks of break, the effects of the  two training sessions were additive. Growth in metrics like how efficiently  their bodies took in oxygen built on   top of progress made during  the first training session.

So by the end of the second training session,   they had made cumulative improvements,  despite substantial time away from the gym. The effects were strong enough for the  researchers to conclude that training   is easier when you have trained  before, even if it’s been a while. Now, that’s a lot to promise for you,  the New Year’s resolution exerciser.

Especially because you’ve  probably been there before. I doubt this is your first year  staring down quitters’ day and   feeling a bit less motivated  than you were on January first. And it’s still not easy.

But one thing research tells us is that results  can vary depending on the kind of exercise you do. In this study, the participants  that focused on strength training   lost more of their gains than those  that honed their aerobic fitness. And even within the aerobic exercises,   the treadmill warriors had more cumulative  payoff than the cyclist superstars.

Which is a shame, because I do not want to run. So gains from different exercises  last for different amounts of time. But even gains from the same exercise can wear   off sooner or later depending on  the intensity of your training.

Another study tested this in a group of older  men described as “healthy but inactive.” Haha. Oh no... it’s me... These participants trained on either a low or  high intensity exercise program for 24 weeks.

Both programs involved strength, power,   and mobility exercises, like cycling and  weight machines, three times per week. The difference between high and low intensity  training was the number of reps, resistance,   and, you know, intensity of those exercises. Once again, nobody’s surprised  that the high intensity group   had greater gains from that training  schedule than the low intensity group.

The interesting thing was how they  compared after months of detraining. At that point, the high intensity group still had   their improved strength and mobility  …but the low intensity group did not. Again, it didn’t go away all at once.

The low intensity participants kept almost half  of their strength after four months of detraining. But 4 months after that,  they were back to baseline. So after completing low intensity exercise,   eight months of inactivity will  put you back where you started.

But if you pick things up sooner than that,   you can start back up in better  shape than you might think. Also, if you completed high intensity exercise,  then your gains will decline from inactivity,   but you won’t go all the way back to  baseline even a full year after stopping. Which means that more intense exercise  seems to stick with you for longer.

But before I get to the data on  the kind of really intense exercise   that competitive athletes are familiar  with, we need to pause for an ad break. This SciShow video is supported by

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And even elite athletes build their detraining  periods into their annual exercise plans. They wouldn’t do that if it were a total loss  of all the progress they made until then. And, in fact, it’s not.

One small study assessed this  pattern in adolescent swimmers. These volunteers each had at least  five years of competitive experience   and had been training six or seven times per week. They were serious athletes.

And even they took four weeks off. After those four weeks, their  overall performance dipped a bit. They came back with a slower stroke  rate and reduced aerobic performance.

But that aerobic reduction  was only by a factor of 1.8%,   and many other metrics were  statistically unchanged. 1.8% matters in a competition that decides  winners and losers over fractions of a second. But thinking about the bigger picture of how many  adaptations your body keeps despite stopping your   regular training, 1.8% deterioration  over a month is impressively minimal. But that’s what happens when you’re still  competing and just took an off season to recover.

The impression we get from our  average viewer is that if you   competed when you were a student,  that might have been years ago. The good news is there could still be some   leftover benefits sticking  around from your glory days. Depending on your physical condition at the  start of detraining, you can take years off   and still have physiological adaptations from that  time in your life when you regularly exercised.

One longitudinal study checked up on  high school hockey players over time   to see how long they retained  their athletic adaptations. While training, players who exercised  more gained more bone mineral density. So the researchers assessed the players’ bones  using x-rays in almost six years of follow ups.

After high school, half of the athletes stopped  playing hockey and lost some bone mineral density. But it was still significantly  higher than non-athletes three   years later at the final follow up assessment. A similar, yet small, study tested female  gymnasts and found that they also had more bone   mineral density than their non-athletic peers  even four years after they stopped competing.

At this point, both former gymnasts  and non-gymnasts in the study were   exercising less than four  hours per week on average. But the gymnasts still had greater bone  mineral density than the non-gymnasts. All of these studies concluded that it takes  time for the benefits of exercise to wear off.

If you find yourself in an annual  cycle of training and detraining,   feeling like you’re going back  to square on every quitters’ day,   hopefully this data shows you  that your efforts weren’t wasted. Your body retains at least some of the benefits   from that time … even if you don’t see  a treadmill again until next January. But don’t let that be an excuse!

Keep Going! It’s better if you keep going! [♪ OUTRO]