Why the 12-3-30 Treadmill Workout is Taking Over Your Social Media Feed

Woman walking on treadmill on incline

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The 12-3-30 workout is a treadmill-based workout that you may have seen when scrolling through social media. This workout routine claims to boost weight loss and burn calories. The draw behind the workout's success is likely due to its simplicity, but proponents claim it is also effective.

If you are curious about the 12-3-30 workout and want to learn more, keep reading. Below we cover how it works and the potential benefits.

What is the 12-3-30 Workout?

Each number in the 12-3-30 workout represents an aspect of the workout's features. This workout lasts 30 minutes while walking at an incline level of 12 and speed setting of 3 miles per hour on the treadmill.

While this makes the workout easy to remember and perform, keep in mind that some treadmills use a different grading system for the incline or do not go up to 12. To adapt the workout for your machine, preferences, or fitness level, set the speed at a challenging walking pace and incline for you.

The idea is to get your heart rate up without running by using the incline setting and a moderately paced walking speed. Make adjustments that suit you as you go.

Benefits of the 12-3-30 Workout

There are some fantastic benefits to doing the 12-3-30 workout consistently. If you only try the workout once or use it a handful of times, it can help contribute to that week's activity level.

The U.S. Department of Health and Human Services recommends moderate-intensity cardio for 30 minutes a day, 5 days a week.Depending on your fitness level, this workout may be moderate or more high-intensity, as a 12% incline is challenging and can push the seemingly easy walking workout into a more vigorous zone. Here's how this workout may benefit you.

Improves Health

As with any form of physical activity, this treadmill workout will improve your health. The benefits of exercise are vast and include increased heart and respiratory system functioning, reduced risks of mental health issues such as depression and anxiety, stronger bones and more stable joints, and bigger and stronger muscles.

Further, consistent exercise leads to better blood sugar regulation, improved hormone balance, better sleep quality, and reduced risks of several diseases such as metabolic syndrome, heart disease, and diabetes.

May Build Some Lower Body Muscle

While resistance training exercise is recommended for the most effective muscle-building activity, you may build some lower body muscle and increase strength if you are a beginner to exercise when you perform the 12-3-30 workout.

Walking at an incline activates your hamstrings, quads, glutes, hip, knee, and ankle flexors. It builds stability in your leg muscles, improving your joint health and daily functioning.

Increases Daily Energy Expenditure

Expending energy through exercise helps balance energy and encourages healthy weight maintenance. Walking on an incline increases the calorie burn compared to walking on flat ground due to the added effort necessary from your muscles.

Each 1% incline grade burns approximately 10 additional calories per mile for a 150-pound person. This would result in over twice as many calories burned walking at a 12% incline compared to walking on a flat surface.

Provides Low Impact Alternative

If you've been searching for a joint-friendly and low-impact cardiovascular workout, consider the 12-3-30 workout. Whether you are a runner or not, working in lower impact forms of training can help reduce overuse injuries while still getting in your cardio workout.

If you have joint pain or issues that prevent you from higher impact cardiovascular work, this workout—which uses incline rather than speed—can help you get your heart rate up and avoid aggravating existing issues. However, note that as a result of the high incline, performing this workout too often may cause stress on joints, muscles, and tendons that aren't typically used.

Provides Cardiovascular Workout

The 12-3-30 workout is a form of cardiovascular exercise. It is considered steady-state cardio, which means that once your heart rate is elevated to a moderate level, you continue performing the activity at that same level before completing the workout. Note that depending on your individual fitness level, your heart rate response to this workout may be higher or lower than what is considered to be moderate.

Steady state training is different from interval training. During interval training, you work out at a high-intensity level and then come back down to a lower pace before repeating a higher intensity interval.

HIIT may be better suited for those newer to exercise, as there are built-in breaks. Over time, as you build stamina and endurance, you can work up to higher intensity, steady state exercise.

If you are new to exercise or consider yourself a beginner, you will want to work your way up to walking for extended periods of time and at an incline. This workout may be too advanced for people new to exercise, and may not be appropriate for those who have chronic issues such as joint pain.

Risks of the 12-3-30 Workout

The 12-3-30 workout is low-risk for those who are active already. As long as you are cleared for basic exercise by your doctor, you have a baseline of cardiovascular endurance, and you do not have injuries, there is minimal risk. However, all forms of exercise carry inherent risks, especially if you have a heart condition. Be sure to discuss your exercise choices with a healthcare provider.

When using a treadmill, attach the safety strap in case of falls. This strap will pull out a key that stops the treadmill if you fall, preventing worse injuries. This is especially important when walking on an incline as the risk of tripping could be higher.

Warm-up before the workout by walking at a slower pace and lower incline. If you feel dizzy or out of the ordinary in any way, stop the activity. Never push past pain, so if you experience joint or muscle pain, stop the workout. Also be sure to hydrate before and during the workout, and rehydrate after you finish.

A Word From Verywell

Physical activity is part of a healthy lifestyle and provides many benefits for your physical and mental health. The 12-3-30 workout is a treadmill-based cardiovascular routine that helps increase daily active minutes and contributes to energy balance. While it is a relatively safe form of exercise, be sure to discuss this workout with a healthcare provider.

Frequently Asked Questions

  • How many times a week should you do 12-3-30?

    The U.S. Department of Health and Human Services recommends moderate-intensity cardio for 30 minutes a day, 5 days a week, but more can provide greater benefits. Because this workout may be moderate for some and vigorous for others, you will likely want to incorporate it 2 to 3 times per week to avoid injury.

  • How do you do the 12-3-30 workout?

    To do the 12-3-30 workout, set your treadmill to an incline of 12 and speed of 3 mph. Walk for 30 minutes to complete the workout. You can adjust the speed and incline to suit your fitness level.

  • Is walking on an incline good for you?

    Walking on an incline activates more leg muscles and burns more calories than walking on flat ground.

  • Is it better to walk fast or on an incline?

    Walking fast or on an incline are both excellent forms of exercise. You can add both to your fitness routine to gain the benefits of each. Walking on an incline provides additional benefits for your leg muscles, potentially building more strength and muscle if you are a beginner.

5 Sources
Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition. U.S. Department of Health and Human Services. 2nd Ed. 2018. 

  2. U.S. National Library of Medicine. Benefits of exercise.

  3. Garduno AC, LaCroix AZ, LaMonte MJ, et al. Associations of daily steps and step intensity with incident diabetes in a prospective cohort study of older women: The Opach StudyDiabetes Care. 2022;45(2):339-347. doi:10.2337/dc21-1202

  4. Franz JR, Kram R. The effects of grade and speed on leg muscle activations during walkingGait Posture. 2012;35(1):143-147. doi:10.1016/j.gaitpost.2011.08.02.

  5. Swain DP, Brawner CA. ACSMs Resource Manual for Guidelines for Exercise Testing and Prescription. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2014.

By Rachel MacPherson, BA, CPT
Rachel MacPherson is a health writer, certified personal trainer, and exercise nutrition coach based in Montreal.