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Is The 8-Hour Arm Workout Worth a Try for Muscle Growth?

Big, defined arms are the envy of many who lift weights. No wonder the late Rich Piana’s 8-hour arm workout caught the attention of many.

The workout claims to significantly increase arm size in just one day by putting them through an exhaustive, marathon session of curls, tricep extensions, and other arm-focused exercises. It sounds extreme because, well, it is.

Eight hours of continuous lifting is not your average day in the gym, and it raises the question of whether such intensity is effective or even safe.

So, should you consider dedicating a whole day to pumping your biceps and triceps?

Here’s a closer look at what this unconventional method entails and whether or not it’s worth trying for those seeking substantial muscle growth.

Who Made The 8-Hour Arm Workout?

The 8-hour arm workout was created by the late Rich Piana, a professional bodybuilder and social media sensation known for his massive size and unconventional training methods.

Piana claimed that he came up with this extreme arm workout back in the early days of his bodybuilding career when he would spend hours at the gym trying to achieve bigger arms.

He believed that by spending an entire day focusing on just one muscle group with high-volume training, he could shock the muscles into growth.

The claims made about this workout are:

  • It can increase arm size by up to an inch in one day.
  • It can help break through muscle growth plateaus.
  • It can provide a change of pace for those who are stuck in a training rut.
  • It can be a fun challenge for experienced lifters looking to push their limits.

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What Does The 8-Hour Arm Workout Involve?

As the name suggests, the 8-hour arm workout involves dedicating a full eight hours to training your arms. Here is what the 8-Hour Arm Workout by Rich Piana entails:

Prep Day

For two days leading up to the workout, you should lay off training your arms. Some experts may recommend laying off training completely; you’re about to put your arms through a grueling day, so they need to be well-rested.

During this time, you should also:

  • Eat lots of complex carbs, protein, and healthy fats to fuel your body for the intense workout (2).
  • Drink plenty of water to stay hydrated (1).
  • Prep 16 protein shakes containing essential amino acids, carbs, and creatine. These will be consumed throughout the workout to keep your energy levels up.
  • Prep your meals for the day, including a protein-packed breakfast, lunch, and dinner.


The Workout

On the day of the workout, it’s best to start early in the morning. Rich Piana recommends starting at around 10 AM and finishing by 6 PM.

That morning, you’re to eat a large breakfast an hour or two before starting. This breakfast should consist of a mix of protein, carbs, and healthy fats.

You might want to block off the entire day on your calendar because you won’t have time for much else.

You might also want to measure your arms’ size before and after the workout to track any gains.

During the workout, you’ll be doing 4 sets of 10-15 reps of a variety of arm exercises. The 8 hour arm workout exercise list has:

  • Skull crushers
  • Barbell curls
  • Single Arm Dumbbell Extensions
  • Barbell/Dumbbell Hammer Curls

You’re to rest for a minute between sets and exercises, consuming one of the pre-made protein shakes during each rest period.

The workout is repeated for eight hours with short breaks every hour to eat a meal or take a bathroom break. The goal is to do about 8 weeks’ worth of arm training in one day.

Read more: Thigh Workout Guide: 7 Effective Exercises for Building Leg Strength

Post Workout

After the workout, you should consume a large post-workout meal and drink plenty of water to replenish your body’s nutrients and hydrate.

Piana recommended spending the rest of the day relaxing and not doing any strenuous activity, as your arms will likely be extremely fatigued.

You’ll also want to measure your arms afterward, to see if there was any significant growth.


Is 8 Hour Arm Day Optimal?

No. An 8 hour arm day is not optimal for muscle growth.

While the workout may provide a temporary increase in arm size, due to increased blood flow, also known as a pump, it’s unlikely to result in long-term muscle growth.

The body adapts and grows from consistent training over time, not from one extreme workout. Additionally, such a prolonged and intense session can put excessive strain on the muscles and joints, increasing the risk of injury (3).

Moreover, the 8-hour arm workout neglects other important muscle groups in the body, leading to an imbalanced physique and potential muscular imbalances which can hinder progress in the long run.

What about the anecdotal evidence of individuals seeing significant growth after trying the 8-hour arm workout?

There are a few reasons why fitness enthusiasts may have seen an increase in arm size after trying the workout:

  • Post-workout swelling and inflammation – the intense and prolonged workout can cause temporary swelling and pump in the muscles.
  • Creatine consumption – consuming 16 protein shakes throughout the day will also mean significant creatine intake, which can lead to increased water retention and a fuller appearance in the muscles.
  • They may have experienced a placebo effect from the hype surrounding the workout, leading them to believe they saw growth when it was actually temporary swelling.
  • They may be advanced lifters who were already close to their genetic potential and saw minimal gains from traditional training methods, making the extreme 8-hour arm workout seem more effective.

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How Long Should My Arm Workout Be?

A 45-minute arm workout may be sufficient for most individuals looking to build muscle. This time frame allows for an adequate amount of exercises, sets, and reps while still leaving room for proper rest and recovery.

More does not always equal better when it comes to training. Other factors to consider to know whether your arm workout is optimal include:

  • Frequency – How often are you training your arms each week? Are they getting enough rest between workouts?
  • Intensity – Are you using appropriate weights and pushing yourself to fatigue during each session?
  • Exercise choice – Are you incorporating a variety of exercises that target all heads of the bicep and tricep muscles?
  • Diet and nutrition – Are you consuming enough calories, protein, and carbs to support muscle growth?

Tips for Growing Your Arms

If you’re looking to increase arm size, here are some tips that may be more effective and sustainable than an extreme 8-hour workout:

  • Train arms 1-2 times a week with at least 48 hours of rest in between.
  • Focus on progressive overload – gradually increase weight or reps each week to continuously challenge your muscles.
  • Incorporate compound exercises like pull-ups, rows, and push-ups that indirectly target the arms, while also engaging other muscle groups.
  • Consume a balanced diet with enough calories and nutrients to support muscle growth (2).
  • Get adequate rest and recovery time for your muscles to repair and grow (4).

Remember, building muscle takes time and consistency. Instead of looking for quick fixes or extreme methods, aim for sustainable and balanced approaches to reach your fitness goals. 

Read more: Your Flat Tummy Workouts Just Got Better With This Guide



  • Is It Ok To Work Arms Everyday?

It’s not OK to work arms every day. Muscles need time for rest and recovery in order to grow. Overworking your muscles can lead to injury and hinder progress (3).

  • Is 2 Arm Days a Week Too Much?

2 arm days a week isn’t too much, provided you’re allowing for adequate rest and recovery between workouts. Beginners should work their way up to this frequency and monitor their progress to avoid overtraining.

In a previous blog: Arm Exercises with Loop Bands , we discussed the benefits of incorporating resistance bands into your arm workouts. Resistance bands can provide a challenging and effective workout while reducing strain on the joints and targeting small stabilizer muscles in addition to major muscle groups.

  • Can I Train Biceps Every 48 Hours?

You can train biceps every 48 hours, as this allows for adequate rest and recovery time between each session. Note that the biceps are involved in many other upper body exercises, so it’s important to consider how often you’re indirectly working them as well.  

For example, if you’re also training your back and shoulders on different days, you may be indirectly working your biceps more frequently than every 48 hours.

  • Can I Train Arms Every 48 Hours?

Yes, you can train arms every 48 hours, as long as you’re allowing enough rest and recovery time between each session. Since the arms comprise multiple muscle groups, it’s important to also consider how frequently you’re indirectly working them through other exercises.

Check out our previous blog: Resistance Bands for Arms for more tips on how to effectively train your arms and build muscle.

The Bottom Line

While the 8-hour arm workout may provide a fun challenge for experienced lifters or a temporary increase in arm size, it’s not a sustainable or optimal method for long-term muscle growth.

For sustainable muscle growth, it’s best to follow a well-rounded training program that targets all muscle groups and allows for proper rest and recovery.

It’s always essential to listen to your body, train smart, and avoid extreme or potentially dangerous methods in pursuit of quick gains.  With that in mind, it’s better to stick to traditional resistance training methods for achieving substantial muscle growth in the long run. 


This article is intended for general informational purposes only and does not address individual circumstances. It is not a substitute for professional advice or help and should not be relied on to make decisions of any kind. Any action you take upon the information presented in this article is strictly at your own risk and responsibility!


  1. Effect of hydration state on strength, power, and resistance exercise performance (2007,nih.gov)
  2. Nutrition for Physical Activity and Athletics (2019,okstate.edu)
  3. Resistance training – preventing injury (2015,betterhealth.vic.gov.au)
  4. Sleep and Recovery (n.d,wm.edu)
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