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0:00You and I both know that I
am not a fitness influencer.
0:02I host a science channel.
0:04So I am here with the relatable fitness content;
0:07the guidance for the average
person who tries to be a little
0:10healthier by making a resolution
to go to the gym every January…
0:13and never makes it through the whole year.
0:15When you, perhaps inevitably, stop exercising, it
can feel like all of that effort was for nothing.
0:20Like you lose the gains
that you worked so hard for.
0:23But there’s research out there
telling a different story.
0:26Studies suggest that even if
you give up exercising after
0:30only weeks of sticking to your goal,
you keep some of the improvements.
0:34You can pick up that good habit
months or even years later and
0:38still benefit from the work you put in before.
0:40As it turns out, your burst of motivation can
help you out for longer than you might think.
0:49You know exercise is good for you, and so do I.
0:52That’s why every year, around January,
0:54we spend just enough time using that
gym membership to justify keeping it.
0:59Many people quit after a matter of weeks.
1:01So many that there’s a name for this time
after a New Year when your gym empties out.
1:05It’s called “quitters’ day.”
1:07So if you’re thinking about dialing the exercise
back right around now, you’re not alone.
1:11Whenever your own personal quitters’ day is,
1:14that’s when you begin the
long process of detraining.
1:17This results in your body slowly losing the gains
you made during your temporary training regimen.
1:22And luckily, it doesn’t all happen immediately.
1:24In fact, some of those gains stick with you
1:27for long enough that your next
gym attempt is more effective.
1:30Now perhaps, you’re watching
this video from a treadmill,
1:33still going strong with
your New Year’s resolution.
1:36But if your resolve is starting to waver,
1:38whatever time you’ve already spent
working on yourself has been worth it.
1:42Let’s say you stick it out for
16 weeks of exercise this year.
1:45If you start in January, that
would bring you to April.
1:49Maybe you quit at that point
and take the next 10 weeks off.
1:52You might think that your resolution
training was all for nothing.
1:56This exact timeline was tested
in people aged 60 and older.
2:00So the resilience that the researchers
found wasn’t just a matter of being young.
2:04Study participants started out completing a
circuit of either strength training exercises,
2:08like what you might do at physical therapy,
2:09or moderate cardiovascular exercises, like
biking, for 20 minutes three times per week.
2:15As the study went on, they ramped up the workouts.
2:18From all that hard work, participants
2:20improved both their cardiovascular
endurance and their muscle strength.
2:24Then, when they stopped,
some of the gains were lost.
2:26Nobody’s surprised by that.
2:28It’s when the researchers looked at which
gains stuck around that things got interesting.
2:32After weeks of detraining,
2:34the participants didn’t all end up back
at their baseline from before training.
2:38They held onto a significant
amount of cardio fitness.
2:42Their recently acquired muscle strength,
on the other hand, went away faster.
2:46So over ten weeks, they were
definitely in a period of detraining.
2:49But it didn’t completely demolish their
progress, particularly for the cardio group.
2:54In fact, when they started retraining again after
2:5610 weeks of break, the effects of the
two training sessions were additive.
3:01Growth in metrics like how efficiently
their bodies took in oxygen built on
3:05top of progress made during
the first training session.
3:08So by the end of the second training session,
3:10they had made cumulative improvements,
despite substantial time away from the gym.
3:15The effects were strong enough for the
researchers to conclude that training
3:18is easier when you have trained
before, even if it’s been a while.
3:22Now, that’s a lot to promise for you,
the New Year’s resolution exerciser.
3:26Especially because you’ve
probably been there before.
3:29I doubt this is your first year
staring down quitters’ day and
3:32feeling a bit less motivated
than you were on January first.
3:36And it’s still not easy.
3:37But one thing research tells us is that results
can vary depending on the kind of exercise you do.
3:42In this study, the participants
that focused on strength training
3:45lost more of their gains than those
that honed their aerobic fitness.
3:49And even within the aerobic exercises,
3:51the treadmill warriors had more cumulative
payoff than the cyclist superstars.
3:56Which is a shame, because I do not want to run.
3:59So gains from different exercises
last for different amounts of time.
4:02But even gains from the same exercise can wear
4:05off sooner or later depending on
the intensity of your training.
4:08Another study tested this in a group of older
men described as “healthy but inactive.”
4:16These participants trained on either a low or
high intensity exercise program for 24 weeks.
4:22Both programs involved strength, power,
4:25and mobility exercises, like cycling and
weight machines, three times per week.
4:30The difference between high and low intensity
training was the number of reps, resistance,
4:35and, you know, intensity of those exercises.
4:37Once again, nobody’s surprised
that the high intensity group
4:40had greater gains from that training
schedule than the low intensity group.
4:44The interesting thing was how they
compared after months of detraining.
4:49At that point, the high intensity group still had
4:51their improved strength and mobility
…but the low intensity group did not.
4:56Again, it didn’t go away all at once.
4:58The low intensity participants kept almost half
of their strength after four months of detraining.
5:03But 4 months after that,
they were back to baseline.
5:06So after completing low intensity exercise,
5:08eight months of inactivity will
put you back where you started.
5:12But if you pick things up sooner than that,
5:14you can start back up in better
shape than you might think.
5:17Also, if you completed high intensity exercise,
then your gains will decline from inactivity,
5:22but you won’t go all the way back to
baseline even a full year after stopping.
5:26Which means that more intense exercise
seems to stick with you for longer.
5:30But before I get to the data on
the kind of really intense exercise
5:34that competitive athletes are familiar
with, we need to pause for an ad break.
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yourself and get a 30-day free trial.
6:26Some of the most intense training sessions
happen in the context of athletic competition.
6:30And even elite athletes build their detraining
periods into their annual exercise plans.
6:36They wouldn’t do that if it were a total loss
of all the progress they made until then.
6:41And, in fact, it’s not.
6:42One small study assessed this
pattern in adolescent swimmers.
6:46These volunteers each had at least
five years of competitive experience
6:50and had been training six or seven times per week.
6:54They were serious athletes.
6:55And even they took four weeks off.
6:58After those four weeks, their
overall performance dipped a bit.
7:01They came back with a slower stroke
rate and reduced aerobic performance.
7:05But that aerobic reduction
was only by a factor of 1.8%,
7:09and many other metrics were
statistically unchanged.
7:121.8% matters in a competition that decides
winners and losers over fractions of a second.
7:18But thinking about the bigger picture of how many
adaptations your body keeps despite stopping your
7:24regular training, 1.8% deterioration
over a month is impressively minimal.
7:28But that’s what happens when you’re still
competing and just took an off season to recover.
7:33The impression we get from our
average viewer is that if you
7:36competed when you were a student,
that might have been years ago.
7:40The good news is there could still be some
7:42leftover benefits sticking
around from your glory days.
7:46Depending on your physical condition at the
start of detraining, you can take years off
7:50and still have physiological adaptations from that
time in your life when you regularly exercised.
7:56One longitudinal study checked up on
high school hockey players over time
8:00to see how long they retained
their athletic adaptations.
8:03While training, players who exercised
more gained more bone mineral density.
8:08So the researchers assessed the players’ bones
using x-rays in almost six years of follow ups.
8:14After high school, half of the athletes stopped
playing hockey and lost some bone mineral density.
8:19But it was still significantly
higher than non-athletes three
8:23years later at the final follow up assessment.
8:26A similar, yet small, study tested female
gymnasts and found that they also had more bone
8:31mineral density than their non-athletic peers
even four years after they stopped competing.
8:36At this point, both former gymnasts
and non-gymnasts in the study were
8:40exercising less than four
hours per week on average.
8:43But the gymnasts still had greater bone
mineral density than the non-gymnasts.
8:47All of these studies concluded that it takes
time for the benefits of exercise to wear off.
8:52If you find yourself in an annual
cycle of training and detraining,
8:55feeling like you’re going back
to square on every quitters’ day,
8:59hopefully this data shows you
that your efforts weren’t wasted.
9:03Your body retains at least some of the benefits
9:05from that time … even if you don’t see
a treadmill again until next January.
9:09But don’t let that be an excuse!
9:11It’s better if you keep going!
