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100 Push-Ups a Day for 30 Days: What Happens to Your Body?

by Jeremy Ethier - July 30, 2022

The "100 pushups a day" challenge sounds cool. But is it really such a good idea? Will you see improvements in your muscle growth and strength, or will you just get injured? Let's see.

Pushups are one of the most effective exercises to increase your strength and build up your upper body muscles like the chest, shoulders, and triceps.

Some people take this exercise to the extreme and commit to doing 100 pushups a day and seem to get impressive results. Heck, even Saitama from One Punch Man did it, and you saw how well that worked out for him.


But ... what really happens to your body if you do 100 pushups a day for 30 days?

  • Will 100 pushups a day do anything?
  • What muscles will grow and by how much?
  • How much will your strength improve?
  • Are there any side effects you should know about?
  • What happens after the 30 days are over?
  • Is it even worth your time and effort?

We'll cover all that — and more — in this article.

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What Kind Of Growth Can You Expect From Doing 100 Pushups A Day?

You're understandably excited about learning what 100 pushups a day could do for your physique.

Before that, though, to maximize your gains and minimize injury from doing 100 pushups a day, it’s important to make sure you do them with proper form. So do check out this past article covering how you could master proper pushup form.

But provided that your form is in check, what kind of growth can you expect from doing 100 pushups a day?

To answer that, let’s take a look at this 2015 paper where researchers measured muscle activity levels during the push-up. The highest activated muscles were the:

  • Chest
  • Triceps
  • Front of the shoulders
  • Core, and
  • Serratus anterior
Muscle groups that will grow from doing 100 pushups a day

These are likely where you’ll experience most of the improvements in terms of size and definition.

As for how much of an improvement to expect in these muscles? Although we’ll dive into the specifics later on in this article, I do want to highlight a 2017 study published in the Journal of Exercise and Fitness that shows just how effective push-ups can be.

The researchers measured muscle size and strength in two groups of untrained subjects:

  • Group 1: Used only pushups during their workouts
  • Group 2: Used only benchpress during their workouts

After 8 weeks, the authors found similar size and strength increases in both groups' chest and triceps muscles. This suggests that, at least for beginners, pushups can be just as effective as the bench press.

Size and strength increases you may experience from doing 100 pushups a day

Warning: Doing 100 Pushups A Day May Cause The Following Side Effects

Now although this may seem promising, there are various side effects to doing 100 pushups a day you’ll want to be aware of, starting with week 1.

Week 1

So based on norms provided by the Canadian Society for Exercise Physiology, men who rank “fair” in terms of their fitness on average can do about 15-20 push-ups in a row.

This means you’ll likely need to do several sets of push-ups to get to a total of 100.

In fact, during the first few days or even the first whole week of the challenge, many of you may not even have the strength to reach a total of 100.

Luckily, this is when something called neural adaptations will kick in to help out. This is a phenomenon where although your muscles won’t have yet grown, your brain will have improved its ability to recruit the right push-up muscles and as a result, your push-up strength should improve quite rapidly throughout this week.

Week one of doing 100 pushups a day

By the way: you may want to check out this article for tips on increasing your pushup strength.

In addition, the most noticeable effect you’ll experience in week 1 is DOMS, which stands for delayed onset muscle soreness.

This refers to the tenderness and soreness you’ll experience in your muscles 1-2 days after exercise. Since in this case your body isn’t used to doing 100 pushups a day, week 1 is when you’ll experience the highest amount of soreness in your chest, shoulders, and arms.

This is normal and should die down towards the end of week 1.

However, if you’re feeling it in your traps and low back, that’s a sign that your form may be off.


Although soreness should die by week 2, another side effect will start to creep up and potentially slow down your progress.

Week 2-3

It might sound counterintuitive, but whenever you workout you're actually breaking down muscle, not building it. It’s during rest when your body recovers and builds your muscles up to be bigger and stronger.

Back in 1997, a group of researchers tried to determine just how long this recovery process takes. They found that our muscles continued to recover and grow for even up to 48 hours after we workout.

Based on this paper and other similar studies, this 48-hour time frame seems to be the average time it takes a muscle to fully recover. So in the case of doing 100 pushups a day, since you’re training the same muscles every single workout, they aren’t getting a long enough break to fully recover.

Doing 100 pushups a day does not give your body adequate time to recover

Because of this, you’ll likely start to experience quite a bit of fatigue in weeks 2 and 3.

Your body and muscles may start to feel more exhausted than normal, and as a result, your pushup performance may even start to decrease.


Psst: here are 4 science-backed strategies you could use to enhance muscle recovery.

This, combined with the next side effects you’ll feel in week 4, can make continuing to do 100 pushups a day extremely difficult and as we’ll talk about later on, potentially not even worth it.

This highlights the importance of a well-structured workout program. Ideally, you want your workout program to push you hard, but not hard enough to run into recovery issues. Not sure how to plan your own training? Well, good news: there's no need to when you have Built With Science programs:

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Week 4

So by the time week 4 rolls around, your body will have taken a beating from the high frequency and high volume pushups.

We’ll cover how much you can expect your muscles to grow after this week, but before that, you may start to notice two things.

#1: Doing 100 Pushups A Day May Cause Muscle Imbalances

The first thing has to do with muscle imbalances. Pushups are great at training the front pushing muscles of your body.

But your back isn’t involved at all. If you regularly train your front muscles without training your back muscles, then the stronger front muscles will over time start to pull your body forward into a hunched-over position with your shoulders rounded forward.

Ideally, to balance this out, you’d want to perform plenty of back work focused on the muscles that’ll help you keep you upright and shoulders healthy — even as you're doing 100 pushups a day.

The following back workouts may help you:

#2: Doing 100 Pushups A Day May Cause Strain On Your Joints

Now the other thing you’ll notice has to do with your joints.

Even with proper form, the repetitive motion of pushups can create a lot of strain, especially on your wrists and elbows.

Your wrists not only need a high amount of mobility to perform pushups on the floor but they will also be loaded with quite a bit of weight that you probably aren’t used to. Because of this, your wrists will be one of the first areas where you notice discomfort.

To mitigate this, you can try to do pushups with handles or dumbbells — anything that allows you to grip it instead of placing your hands flat on the floor.

As for your elbows, pay attention to the bottom position of your pushup. If they don’t remain aligned directly on top of your wrists as you perform the pushup, then you’re creating more stress on your elbow joints.


Normally this is fine, but if you’re doing 100 pushups a day and not allowing your joints to rest, it’ll very quickly start to take its toll on your elbows.

100 Pushups A Day Results

So, in the pushup study I mentioned at the beginning, the subjects weren’t doing anywhere near 100 pushups a day. Instead, they were assigned 3 sets of pushups to failure twice a week.

The max number of push-ups they could do in a row was around 30 reps, which would equate to about 90 push-ups being done each session. A total of roughly 180 push-ups per week. Although this sounds like nothing compared to 100 push-ups a day, they still experienced significant growth.

Over the course of 8 weeks, they experienced the following:

  • Chest growth: 18.3% increase in the muscle thickness, equating to about a 3 mm increase in thickness
  • Triceps growth: 9.5% increase in growth, equating to about a 3 mm increase in thickness

The researchers mentioned that this rate of growth is similar to other past studies.

So, if you halve these numbers, you can get a rough sense of the kind of growth you can experience after a month of doing pushups just twice a week.

Muscle size increase you could expect from doing 100 pushups a day

If you were to do 100 pushups a day, would you experience more growth?

Well, I’d expect it to be similar or perhaps even less because you’re not giving your body adequate time to recover and grow. In addition, keep in mind that after these 30 days, if your body gets stronger, it will need more of a challenge to continue growing.

Eventually, standard pushups just won’t be enough, and you’ll have to start incorporating bands or added weight.

Bottom Line: Is Doing 100 Pushups A Day Good Or Worth It?

Now as for whether this is all worth it or not, honestly, I would not recommend the standard approach of doing 100 pushups a day for 30 days, every day without rest. It just causes too many recovery issues and lacks the progression you need to continue seeing results past 30 days.

One benefit it does provide however is it gets you in the habit of exercising. It’s a great way to get your foot in the door and build momentum.

That said, this routine can definitely be made far better.

With a few tweaks, it has the ability to provide even more growth with less effort and less strain on your body. I will be working on an article that shows you a “better” way to execute the 100 pushups a day challenge, though, and I'll provide a link once it's done. Keep your eyes peeled for it!

In the meantime, if you’re looking for a proven, science-based program that guides you every step of the way to your dream body, just take my analysis quiz below to discover the best approach for you and your specific body:

Click the button below to take my analysis quiz to discover the best program for you:

But that’s it for today! Before you go, though, I'd highly recommend you to check out the following articles:

By the way, here’s the article summed up into a YouTube video:

What Happens To Your Body After 100 Push-Ups a Day For 30 Days

100 Push-Ups a Day for 30 Days: What Happens to Your Body?