Does LESS Exercise Make You MORE Fit?

By Dr. Justin Marchegiani

High intensity interval training, called HIIT for short, has taken the health and fitness world by storm. The concept is simple: by working out harder, less often and for shorter lengths, you can actually maximize your fitness returns. Research shows HIIT can burn fat quicker and substantially increase performance. The best part? The time commitment is minimal. Say goodbye to your daily hour at the gym, and hello to HIIT!

How to Do High Intensity Interval Training

High-intensity interval training is a way of exercising through a repetition of short bursts of high-intensity exercises followed by a brief period of recovery. The HIIT sequence of “burst and recover” is generally repeated for a duration of 20-30 minutes.

HIIT can be applied to both cardio and weight training. In a treadmill setting, a HIIT session would involve alternating between high intensity sprints and a slower jog, or even a brisk walk, during the recovery period.

High-intensity interval training differs from traditional consistent state exercise in which you’d keep a similar pace, exerting constant energy for the duration of your session.

If you’re looking to burn fat, increase endurance, or otherwise boost your health and fitness with but less of a time commitment, HIIT is for you!

Is HIIT right for you? Click here to ask a functional medicine doctor!

Benefits of High Intensity Interval Training Over Traditional Methods

  • Burn Fat More Efficiently: A recent study compared the impact of HIIT workouts versus steady state exercise on body fat and musculature. While a HIIT workout burns less calories during the course of the session, a HIIT routine still results in more fat loss overall. The study also found that high intensity training workouts more efficiently build muscle and improve metabolic function.
  • Cardiovascular Health: Interval training is being studied for its effects on cardiovascular health. Interval training regimens, such as HIIT, have profound improvements on VO2max which is one of the best indicators of cardiovascular health. By exerting more energy and pushing your heart rate during the HIIT “bursts,” you condition your heart and over time make it much stronger and more resilient.
  • Anti-Aging: The relationship between physical activity and life expectancy is well known. More recent research has shown that one way in which exercise increases life expectancy is by activating telomerase, an anti-aging enzyme. HIIT not only increases telomerase, it also reduces a protein responsible for premature aging and tumor suppression. 
  • Capillary Function: Resistance-based interval training specifically benefits blood flow, blood vessel dilation, and capillary density. A study from 2004 found that HIIT increases capillary density by 20% which means the body is better able to feed sugar and oxygen to the muscles than in a person who is doing steady state exercise. 

Choosing the Best High Intensity Interval Training Workout For You

Here are a few HIIT workouts to choose from. Have a look and see which one matches your skill level and interests! As your skill grows, you can modify these plans to include more high intensity bursts.

IF YOU: are very fit, have little time, like to run

Tabata Running: Tabata training is a very popular form of HIIT consisting of 8 rounds of high intensity exercises. Intervals are 20 seconds on, 10 seconds off. Including a warm up, this HIIT session is done in under 10 minutes! For an experienced runner, it would look like this:

  • Start with a 3 minute warm up.
  • Then, 8 rounds of:
  •  20 second ultra-intensity sprints
  • 10 second light jogging.

IF YOU: are moderately fit, flexible timing, like to cycle

If you have 30 minutes to spare and like to cycle, this method is for you! The intensity can be adjusted to match your skill level. The basics of this cycling HIIT workout for someone of a moderate fitness level:

  • 3 minute warm up.
  • 60 seconds of cycling FAST at maximum resistance.
  • 75 seconds cycling slow at a low resistance.
  • Repeat for 12 cycles

IF YOU: are new to fitness, have moderate time, want to incorporate strength training

For someone new to fitness and interested in the benefits of HIIT, a 45-minute beginner’s workout would look something like this:

  • 5 minute jump rope warm-up.
  • 8-reps of weight lifting
  • 1 minute of mountain climbers
  • 1 minute jumping jacks.
  • Repeat this circuit until you have hit 45 minutes

Ready to take your health to the next level? Click here to work with a functional medicine doctor!


The entire contents of this website are based upon the opinions of Dr. Justin Marchegiani unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Justin and his community. Dr. Justin encourages you to make your own health care decisions based upon your research and in partnership with a qualified healthcare professional. These statements have not been evaluated by the Food and Drug Administration. Dr. Marchegiani’s products are not intended to diagnose, treat, cure or prevent any disease. If you are pregnant, nursing, taking medication, or have a medical condition, consult your physician before using any products.