Cardiovascular health is an essential part of fitness. Whether your goal is to lose fat, relieve stress or improve heart health, cardio is key to your training program. The options can be overwhelming and it’s not easy to know the best fit for your fitness level and goals. This article will look at two popular forms of cardio training: High intensity intervals (HIIT) and Low intensity steady state (LISS).

Both can take the form of running, biking, swimming, rowing and so on. They provide many of the same benefits, however HIIT and LISS use contrasting methods. Here’s a guide to help you choose your next cardio training session. First, let’s review these two training options.

High intensity interval training (HIIT) focuses on short bursts of all-out effort followed by a period of low intensity effort. An example of a typical HIIT session would be 8-10 intervals on the stationary bike in which 30 seconds of maximal effort is followed by 90 seconds of low effort. On the other hand, low intensity steady state cardio (LISS) requires low to moderate effort at a constant pace for an extended period of time. A LISS workout might consist of a 40 minute swim at 50-70% max heart rate.

To understand which option fits best, let’s consider their individual strengths and weaknesses.

HIIT

If you enjoy a change of pace, the feeling of working hard, and struggle to find time for cardio, then interval training may be for you. A 2017 meta analysis study found HIIT and LISS to provide similar weight loss benefits, however HIIT requires less training time (1).

With busy schedules, many people choose HIIT for a lower time commitment. Dedicating 20 minutes per session a few times a week may be a more manageable option than longer low intensity sessions. At first glance it seems high intensity sessions are the right option for everybody, why would you spend more time on cardio if you don’t have to?

A big drawback is HIIT simply asks more of the body than LISS, working at high intensities puts high levels of stress on the body requiring more recovery time (2). Engaging in a HIIT session may feel great but at a cost, it may prolong recovery time enough to impede on your normal resistance training program. In addition, the nature of HIIT puts us at risk for injury, especially when considering exercise selection. One wrong step while sprinting for example, can cause an injury halting further cardio or resistance training.

Some options for HIIT:

LISS

LISS is a great method for beginners gaining experience doing cardio or somebody getting back into training. The nature of low intensity exercise allows for quicker recovery than something like HIIT, with faster recovery more sessions are possible each week. In addition, low intensity cardio sessions can be social and talking while running or biking may help adherence.

A LISS session should be a minimum of 30 minutes at 50-70% max heart rate, a quick way to find this training zone is the talk test; you should be able to comfortably maintain a conversation. When choosing exercises for LISS sessions keep in mind running is very common since it’s accessible and doesn’t require equipment, however the high impact of running over time is tough on the body. Other modalities like biking, swimming, and walking are low impact options for cardio.

Some options for LISS:

Putting it all together

A comprehensive program consists of strength training and a combination of cardio methods like HIIT and LISS. Both of these approaches to cardio encourage a greater work capacity which allows the body to perform in the gym for longer and at higher intensities. At Hyatt Training we create custom programs often including both HIIT and LISS to provide the body with varied stimulus, helping clients reach their goals.

As you can see the methods of HIIT and LISS are contrasting, instead of thinking of one as better than the other think of them both as tools to help reach your goals. It’s important to understand the best form of cardio is the one most adhered to. Choose a cardio training program you can stick to over a long period of time. Also, cardio should not be used as a main source of fat loss, it is a tool to use in conjunction with good nutrition and a resistance training program.

You may need both HIIT and LISS to stay interested and on track with your goals. LISS may be your preferred method but you find yourself with only 10-20 minutes of free time, you can still get something out of it with a high intensity session. Whether HIIT or LISS is more your style don’t be afraid to try something new and change your training sessions, instead of running challenge yourself with different modalities like swimming or rowing.

https://www.ncbi.nlm.nih.gov/pubmed/28401638
https://link.springer.com/article/10.1007/s40279-013-0066-5

Hyatt Training is a collective of certified, enthusiastic and innovative personal trainers in Portland, Oregon. To read more exercise-related posts like this one, follow this link.