While scrolling on social media may make you more likely to mindlessly wander into traffic, research shows it may also decrease our performance in the gym.

While we know spending time on Instagram – wondering how people take so many damn vacations – isn’t the most productive activity, it turns out it can actually cause a bit of mental fatigue which impacts our physical performance.

This is not the first time a paper looked into the effect technology use has on mental fatigue and exercise performance. A study recently found that performing a mentally fatiguing computer-based task for 20 minutes before lifting resulted in 17.2% fewer squat reps performed over three sets – a notable amount!

So let’s see if scrolling on social media had a similar effect on performance.


The purpose of the reviewed study was to examine if 30 minutes of smartphone-based social media use affected mental fatigue, squat performance, motivation to train, perception of effort, and blood lactate in 16 recreationally trained men and women. 

The reviewed study was a single-blind (i.e., researchers were blinded to conditions) crossover design, and was completed over four laboratory visits. 

The only difference between conditions was that subjects in the phone condition were required to spend 30 minutes of continuous activity engaging in social media networks (e.g., Facebook®, Instagram®, Twitter®).


Overall, mental fatigue due to smartphone usage impaired Smith machine squat rep performance over three sets at ~45-55% of 1RM.

While HRV (heart rate variability) perceived recovery, and blood lactate were not different between groups, smartphone use increased mental fatigue and decreased total reps completed.

Overall, these data suggest that social media use on a smartphone immediately before training can decrease volume performance, specifically how many reps you may be able to perform.


It’s probably a good idea to avoid long-lasting (i.e., at least 30 minutes) phone-based social media engagement and any prolonged cognitive activity before training.