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A guide for personal trainers

It's A HIIT (Workout): A Guide For Personal Trainers

High Intensity Interval Training (HIIT) is quite a popular training method in the health and fitness industry. In fact, according to ACSM Worldwide Survey of Fitness Trends for 2018, HIIT is the top fitness trend. A HIIT workout is incredibly efficient and provides many health and fitness benefits. However, if the practitioner does not properly screen clients and design the workout with a safety-first mindset, this mode of exercising can be quite dangerous. In this article, we shall explore some of the basic science behind the HIIT workout, how to safely apply the workout, and how to review an effective circuit.

Science behind HIIT

The HIIT workout is centered on exercise principles for the human body: anaerobic training, excess post-exercise oxygen consumption (EPOC), and movement proficiency. Anaerobic training consists of high intense, intermittent bouts of exercise . EPOC is when your post-workout oxygen demand remains higher than pre-exercise levels. Movement proficiency is when one can complete bodyweight patterns such as, but not limited to, the squat, lunge, push up, pull up, or plank consistently without correction of the pattern. Now, let’s tie the three points together. If you are exercising with high proficiency throughout a circuit which requires intermittent high intensity bursts, then you create an EPOC, which boosts your metabolism

A guide for personal trainers 1

Time is definitely a major factor when designing exercises in a HIIT workout. If the time or amount of reps are too short, then your client can not increase their heart rate to experience optimal anaerobic demand. If the time length of the exercise is too long, then the client cannot sustain their high heart rate and pulmonary demand. The sweet spot for “working time” in a HIIT workout is 20-30 seconds per exercise with 10-15 seconds of recovery between exercises. Simplicity is key with exercise selection. Choose a basic exercise like the jump squat. The participant can complete many reps in the 20-30 second window as opposed to a complex exercise like the kettlebell windmill.

How to apply

The first step is to risk stratify your clients for any orthopedic/medical limitations. Pay special attention to any cardiovascular limitations. Once the client is medically cleared, test the individual’s fitness and conditioning capacity. We could dedicate several articles to choosing an ideal fitness and conditioning test, but here are some key physiological responses to test:

  • Obtain and sustain max heart for 10 seconds
    • A HIIT workout is based on anaerobic threshold. The best way to obtain that level of work is elevating the heart rate close to target max heart rate.
  • 60 second plank
    • The plank test is a great way to observe a client’s trunk stability. If a client cannot hold a plank for 60 seconds, I do not recommend adding resistance to their body, especially in a HIIT workout.
  • FMS screen
    • FMS screening is recommended for testing movement quality. If movement is poor do not place that client in a HIIT workout.
  • Basic agility (testing athletic motor coordination)
    • Agility testing is recommended to observe if the client possesses the capacity to change directions without trouble.
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Sample workout

Alright, the clients are cleared and now let’s get down to business. “Four Corners” is a classic HIIT workout that is easy to apply in a group training environment. In Four Corners there are two exercises per corner. Each exercise is 30 seconds in duration with a 10-second recovery and a 60-second recovery between rounds. Sounds simple, right? As a fitness professional, there are multiple ways you can add difficulty to this circuit without adding any weight, increasing reps, or extending the working time.

Corner 1

  • 180-degree jump squats
  • Plank march

Corner 2

  • Plank on the Bravo Functional Trainer
  • Hold medicine ball overhead while running in place

Corner 3

  • Shuffle to sprints
  • Cable pulldown on Bravo Functional Trainer

Corner 4

Sequencing for the HIIT workout

  1. Complete all exercises clockwise
  2. Complete all exercises counter-clockwise
  3. Complete all A’s first then B’s
  4. Complete all B’s first then A’s

I hope this article is beneficial in applying a safe and effective HIIT program with your clients. Remember, keep the workout simple. Simplicity can create the most challenging and intense workout. 

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