Why Are My Muscles Shaking During a Workout?

Why Are My Muscles Shaking During a Workout?

We’ve all done workouts that leave us exhausted. We could be out of breath, sore, tired, and out of sorts.

But, have you ever finished up a workout, held out your hand, and it wouldn't stop shaking?

Or maybe you are someone who shakes mid-set during a workout. You may wonder what this is and why it's happening.

Is it an injury? Is it something that could be dangerous? What is actually happening when our muscles shake?

Let's take a deeper look into what this is, why it happens, and how you can work to prevent it.

Why Do My Muscles Shake During My Workout? 

When your muscles begin to shake, it's likely because you are pushing yourself in your workout. It's a sign that you are taking your muscle tissue to a point of failure. That's a great thing! The more you challenge yourself, the more likely it is that you will progress. 

However, there are many reasons that your muscles could be shaking. So, what are some of the most common reasons that this happens.

Muscle Shaking From Muscle Fatigue 

In my experience, this is the most common reason that somebody’s muscles will shake during a workout. When you work out, you break your muscle tissue down.

This could be part of what wears you out and causes your muscles to shake. The harder you work in your training session, the more likely your muscles are to shake (1). The consistent contractions from your muscles could be a likely culprit.

Muscle Shaking From Dehydration

Hydration plays a huge role in many functions in the body. Some of these include your energy levels and muscle contractions (2).

A proper balance of electrolytes is important to make your muscles contract properly. If your body doesn't have this balance, then it can cause your muscles to twitch and shake. This can especially be common when you train in the heat. The temperatures could cause you to sweat more and lose more electrolytes.

In order to prevent this from happening, it's best to stay hydrated.

Muscle Shaking From a New Stimulus

When you are trying new styles or types of workouts, then your muscles might shake. This can happen because your body is simply not used to the resistance.

This can also happen when you add more volume (weight, reps, sets), try new exercises, or increase your activity as a whole.

When you give your muscles a new challenge, it's common for them to shake (3).

What To Do When Your Muscles Shake During Your Workout 

So, what should you do if your muscles begin to shake? Well, the good news is you usually don't have to stop what you're doing. In my experience, pushing through these tough moments can be beneficial.

When your muscles shake, your body is likely trying to get more out of your muscles.

That's why it can be important to keep pushing yourself. When you push through and complete the exercise, you are training your body to be stronger.

Now, this is a case where you should use a spotter. This is simply to keep yourself safe and to help you out if you cannot complete a rep.

But even if you do not complete the exercise, it's a chance to try it out and get your body used to the resistance.

With that being said, I want to make this very clear: Listen to your body!

Sometimes this shaking simply means that your body isn’t strong enough yet! It's important to keep trying, keep progressing, and keep pushing yourself as time goes on.

How Do I Stop My Muscles From Shaking? 

If your muscles are shaking, then it doesn’t mean anything is wrong with you. If anything, it's a good indication that you're pushing yourself to get stronger!

If you ever get to a place where you are nervous or uncomfortable when your muscles are shaking ... there are 3 things that I recommend you try in order to keep it from happening when you work out: 

• Starting light and working to increase your weights slowly over time 

 Warm up before your weight resistance training

 Drink water and use electrolytes before, during, and/or after training

For the most part, these are all things I recommend doing in your workouts anyway.

Just make sure to fuel your body with the proper nutrients it needs to recover and perform pre and post-workout too. This can be very helpful for fueling your performance.

One Last Tip When Your Muscles Shake

Like I said, muscle shaking during your workout can be a good thing! It often means that you're properly fatiguing your muscles. This also means you're pushing yourself hard enough to see progress.

If you've driven your body to this level of fatigue, the next step will be proper recovery. A lot of people have no problem working out and working hard. However, exercise is only one component to seeing good results with your fitness goals.

Another big factor in your results is your nutrition. Part of your nutrition is making sure you're recovering properly after resistance training. This is where a post-workout protein and carbohydrate can be beneficial.

At 1st Phorm, we offer the Post Workout Stack, which I personally use after every workout! The Post Workout Stack contains Phormula-1 and Ignition.

Phormula-1 is a whey protein isolate, designed to digest rapidly to stimulate quick muscle repair.

Ignition is a rapid digesting source of carbohydrate that also contains a lot of the vitamins, minerals, and electrolytes your body loses during training. Ignition is designed to replenish your muscle's energy stores and allow your muscle to accept more protein and nutrients after a workout.

It's a simple combination that you mix together with water after your workouts. Since I started taking it, I've noticed a big difference with my recovery, soreness, and overall progress. I've also noticed it make a difference for muscle shaking and twitching I can have after workouts!

Not to mention, the flavors are incredible. I'm a huge fan of the root beer float flavor because it tastes just like ice cream and root beer!

Now, obviously, post-workout nutrition isn't the only part of your overall diet. That's why we also offer the 1st Phorm App!

The 1st Phorm App simplifies the process of seeing results. It's a complete all-in-one tool for workouts, nutrition, and more! Inside the app, you'll get instant access to:

• 1-on-1 messaging with your own certified advisor to help you reach your goals

• Custom nutrition programming and an easy way to track and log your food

• Result monitoring through body metrics and measurements to make sure you're seeing progress

• Daily live streams and instructional exercise videos to keep learning and improving

• A culture and community of accountability and support to keep you motivated along your journey

…and so much more!

But, if you have any other questions in the meantime, reach out to us!

You can reach our team of NASM Certified Personal Trainers and Certified Nutrition Coaches any day from 6 AM to 10 PM Central. Just give us a call at 1-800-409-9732 or shoot us an email at CustomerService@1stPhorm.com!

If you’re ready to take your results to the next level, just download the 1st Phorm App and get started today! You can also check out the Post Workout Stack here.

1st Phorm Post Workout Stack


(1) Lippold, O. “The tremor in fatigue.” Ciba Foundation symposium vol. 82 (1981): 234-48. doi:10.1002/9780470715420.ch14

(2) Yu-Yahiro, J A. “Electrolytes and their relationship to normal and abnormal muscle function.” Orthopedic nursing vol. 13,5 (1994): 38-40. doi:10.1097/00006416-199409000-00008

(3) Son, Hyewon et al. “Analyses of physiological wrist tremor with increased muscle activity during bench press exercise.” Journal of exercise nutrition & biochemistry vol. 23,1 (2019): 1-6. doi:10.20463/jenb.2019.0001