HIIT Twice a Day – Downsides and a Detailed Guide

It is never a good idea to do HIIT twice a day. The recommended frequency is to do it 3-5 times a week with a proper rest in between.

Anything more than that can be dangerous for your health.

In this blog, we will discuss different reasons why HIIT twice a day is bad? What you can do instead of HIIT if you want to workout more than once a day? and some other important questions related to the frequency of high-intensity interval training.

Why HIIT Twice a day is Bad?

HIIT twice a day is bad because of 2 major reasons:

  1. The danger of over-training muscles, which can lead to injury, and
  2. The potential too much release of cortisol which can lead to several health issues like decreased immunity, weight issues, and heart problems!

Check out the disadvantages of overdoing high intensity interval training here.

What can you do instead of HIIT twice a day?

According to experts, in a 5 minutes video below, if you want to workout twice a day, the best way to do it is to divide your workout into 2. Do one half at one time of the day and the other half at another time of the day.

This way you can avoid over-training and gain extra benefits from exercising.

Some other Important FAQs related to frequency of high intensity interval training:

1. How Intense is HIIT?

HIIT is so intense that it starts pumping your heart fast within seconds. It tests your endurance to the fullest and regular short breaks are required just to catch the breath a little.

HIIT doesn’t allow you to procrastinate between workouts. You are on the clock. The time of exercises and the time of rest between exercises in HIIT is preset and you have to strictly follow them in order to call your workout a high-intensity interval training workout.

2. What is the most Intense HIIT?

The most intense HIIT is Tabata training. It’s an endurance enhancing protocol ideal for athletes and people in weight loss program for whom time is the most important factor, and they want to get done with working out as soon as possible.

A Tabata session alternates between 20 seconds of exercise and 10 seconds of rest for 4 minutes straight. At the end of 1 session, if you are a beginner your breath will be all over the place.

3. How long should your HIIT workout be?

The sweet spot of HIIT workout a day is somewhere between 20 to 30 minutes a day, but for Tabata, it is better to keep your sessions limited to not more than 5 sessions i.e. 20 minutes a day. And do take a break between every 4 minutes session.

4. What are two downsides to completing a HIIT workout everyday?

The two downsides to doing a HIIT workout everyday are:

  1. It can lead to over-training, which can cause injuries and setbacks in your fitness progress.
  2. Your muscles need recovery after intense workout. Doing HIIT everyday can hamper that recovery and lead to burnout and health problems.

5. Who shouldn’t HIIT?

Following are the people who shouldn’t HIIT:

  • People who are injured.
  • Women who are pregnant.
  • People suffering from serious heart issues.
  • Someone suffering from diabetes, especially those with peripheral neuropathy.

6. Should you do HIIT on off days?

Yes, you can do HIIT on off days but not like a regular workout. You should only do it to keep yourself active on a rest day.

Check out our detailed guide about hiit on rest days and how you can spend your off days active.


This article discussed the possible downsides of HIIT twice a day.

It also provided a detailed guide on how intense an HIIT workout is, why HIIT more than 3-5 times a week is bad, and how you can practice HIIT on your off days.

Some other important issues related to over-doing HIIT were also discussed.

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