What is Peripheral Heart Action Training (PHAT)?

What is Peripheral Heart Action Training (PHAT)?

The key to finding a good fat loss training program is that it should elevate your heart rate, raise the metabolism and challenge the muscular system in a way that stimulates muscle build.

Peripheral heart action training, or PHAT, is an advanced training system that has its roots firmly set within circuit training. It uses an intense, systematic approach to both burn fat and build muscle. It isn’t for everyone  – but if you fancy a challenge and you’ve got a good base of fitness then this might well be for you.

What is PHAT?

One approach to exercise that has lasted the test of time is that of circuit training. Over the years it has been adjusted, adapted and re-marketed but it’s methodology has always remained the same.

Originally introduced by Arthur Steinhaus in the 1940s, it has become one of the go-to ways of improving body composition in athletes and general public alike. More so since the the 1960s when pioneering Sports coach Bob Gadja began to use it on a regular basis.

As an intense but simple approach, peripheral heart action training is purposely designed to elevate your metabolism by ordering each of your exercises in a way that blood is continually moving from one area of your body to the next. It does this for the duration of the workout with minimal rest in-between, forcing your body to work hard.

To maximize the effects on the body, PHAT specifically organises exercises so that they alternate from upper body to lower body and back again. This is different from many other circuit-style approaches.

By paying more attention to the layout of the workout, you can limit lactic acid accumulation within one muscle. This in turn reduces blood pooling and localised fatigue. You’ll be to complete more work in a given time as you provide each muscle group with rest whilst another is being worked.


How to Set Up A PHAT Workout

One of the benefits of peripheral heart action training is in its ability to adapt based on user needs. It can be short and sharp or longer in duration is needed. You can cover all major muscle groups within one session or focus on just a few – it’s really up to you and your individual goals.

The basic rules though are that you avoid singular joint exercises such as bicep curls and leg extensions and instead focus your attention on mutli-joint pushes, pulls, carries or drags.

Aim for around  5-6 different exercises and complete 12-15 reps per exercise. Again, make sure that you alternate between extremities to maximize results. As mentioned, upper body to lower body works well as a ‘non-competing’ approach but you can play around with this to suit.

Perform each exercises for a set time period instead of reps – 30 second intervals works well as it allows a challenging load to be used in each exercise, but with minimal central nervous system fatigue. Give yourself 30 seconds rest time in-between each exercise to allow systemic recovery to take place.

Once you’ve finished all of the planned exercises, rest 1-2 minutes and repeat. It’s up to you how many times you repeat it, but typically 2-3 full circuits is enough to stimulate an effect. Overall, you should be aiming for an intensity of around 80-90% of your maximum. 

If your goal is to improve cardiovascular fitness and optimize body composition then 3-4 PHAT training sessions is sufficient per week. Any less and you won’t maximize results; any more than that and you run the risk of excessive fatigue, non-functional overreaching or overtraining.

Each session can include different exercises to keep you interested. This also allows muscles to be overloaded in a different way each time.


What Are the Benefits of PHAT?

By elevating your heart rate, breathing rate and other autonomic functions you’ll invariably increase your metabolism. Done on a regular basis this can improve your ability to oxidize fat leading to improvements in body composition.

You’ll also improve your cardiovascular health and fitness too. In fact, studies have shown that when compared to traditional high-intensity interval training, PHAT is a superior method for improving strength, maximal oxygen uptake and cardiovagal markers of autonomic control [1].

The use of compound, multi-joint exercises allows you to cover more muscle groups in a session than other similar approaches and this will improve local muscular endurance.

Example PHAT Workouts

Workout #1
  • A1. Deadlifts
  • A2. BB Military Press
  • A3. DB Lunges
  • A4. Pull-ups
  • A5 DB Incline Bench Press
Workout #2
  • A1. Goblet squats
  • A2. Press-ups
  • A3. TRX Leg Curl
  • A4. Neutral grip pull-down
  • A5. Physio ball roll-outs
Workout #3
  • A1. Jump squats
  • A2. Chins
  • A3. Romanian deadlift
  • A4. Low Row
  • A5. DB Step-Ups


  1. Piras, A et al. Peripheral heart action (PHA) training as a valid substitute to high intensity interval training to improve resting cardiovascular changes and autonomic adaptation. Eur J App Physiol. 2015; 115(4): 763-773