12-3-30 Treadmill Workout: The Only Exercise You’ll Need for Weight loss in 2024

A man running on a treadmill

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The 12-3-30 treadmill workout involves walking for 30 minutes at 3 miles per hour on an incline of 12%. While it sounds like an easy half-hour walk on the treadmill, it’s a challenging workout. However, it has several benefits including weight loss, increasing fitness and boosting stamina.

Now that you know what you’re in for, here’s how to do the workout safely.  

Benefits of the 12-3-30 Treadmill Workout 

If you don’t know, the 12-3-30 Treadmill workout trend was started by Social Media Influencer and YouTuber Lauren Giraldo in 2019. She shares her progress since starting the workout in a video that now has 2.8 million likes. She lost 30 pounds and has kept it off with just the 12-3-30 treadmill workout. It was a game changer for her and has been for many people.

Some of the benefits people say include: 

  • Helps with weight loss
  • Increases stamina
  • Builds lower body strength 
  • Improves cardiovascular fitness
  • Burns fat
  • Strengthens bones 
  • Improves balance 
  • Increases stamina 
  • May help with joint pain

In her video, Giraldo says she does the workout about five times a week, which fulfills the U.S. Department of Health requirements. According to their Physical Activity Guidelines for Americans, adults should do at least 150 minutes of moderate-intensity physical activity to gain substantial health benefits. For weight loss, you’ll need to push it up to 300 minutes and ensure you burn more calories than you eat. 

How to do the 12-3-30 Treadmill Workout  workout Safely

As much as this workout is a game-changer, safety should always be your priority. If you’re a beginner, start slow. If you have knee or back problems, some people have reported increased pain from this exercise because of the intensity. Walking on that high incline puts a heavy load on your back, and you need strong hip, thigh and core muscles to prevent aggravating your knees or other joints. For this reason, you need approval from your doctor or a health professional before attempting the exercise. Here are a few tips to help you enjoy the benefits of the workout without straining yourself or getting injured: 

Start Slow

You’ll need to work up to 30 minutes with some practice over a few weeks. Start by walking at least 30 minutes a day on normal terrain or on the treadmill. After three weeks, try a rolling hill or rolling incline workout. This involves increasing the incline every two minutes. For a 20-minute rolling hills workout, start at 2% incline then work your way up 2% every two minutes. When you get to 20 minutes, you would have increased the incline by 8%. 

Once you’re comfortable with this workout, try the workout for 30 minutes at 3 miles per hour on an incline of 6%. After this, you’re ready for 12-3-30. 

Stretch First

Always stretch before any physical activity. Your body needs time to warm up before intense physical movements. Go for a dynamic warm-up, one study shows that dynamic stretching can make your training session more enjoyable by reducing perceived effort. 

Pay Attention to Form

Try not to place your hands on the treadmill’s rails or front display while you walk, and swing your arms in the opposite direction from your legs. You can lightly place your fingertips on top of the rails or hover your arms over them if you’re having trouble balancing; just don’t put your entire weight on them.

Listen to your body

Slow down if you’re struggling to maintain good form or feel like you’re running out of breath. You may need to practice longer before doing the full 30-minute workout. 

Increase the Incline or time to prevent Plateau

Eventually, your body will get used to the workout as you become stronger. You may need to increase the intensity or time to prevent a fitness plateau. If you’re doing the 12-3-30 treadmill workout for weight, it’s a good idea to change up the routine and add other exercises. 


Drink plenty of water before, during, and after the workout. Proper hydration can protect you from fatigue, dizziness, and other health issues, especially when working out intensely.

12-3-30 Treadmill Workout : Step by Step 

Man running on treadmill

Here’s how to do the 12-3-30 treadmill workout: 

1. Warm-up 

Before starting the workout, warm up by walking or jogging at a slow pace for 5-10 minutes. This will help increase blood flow and reduce the risk of injury.

2. Set the Incline 

Set the incline level to 12% (or the highest level you feel comfortable with) to simulate uphill running and target your legs, glutes, and cardiovascular system.

3. Set the Speed

Start at 3 mph (4.8 km/h) and gradually increase it to 3.5 mph (5.6 km/h) as you get more comfortable. Avoid going too fast so you cannot maintain a steady pace throughout the workout.

4. Time Intervals

In your first attempts, you can start with three 10-minute intervals. After each interval, take a 5-minute break to rest and recover before starting the next one. During these breaks, stretch your muscles, hydrate, and adjust the incline or speed if needed. Eventually, you’ll be able to go for 30 minutes without stopping. 

5. Monitor Your Heart Rate 

 Keep an eye on your heart rate during the workout using a heart rate monitor or the built-in sensors on your treadmill. Aim for a moderate intensity where you’re breathing hard but still able to hold a conversation. Adjust your speed or incline accordingly to stay within this zone.

Man jogging on treadmill

6. Remember Proper Form

 Maintain proper running form throughout the workout. Keep your posture upright, engage your core, and land midfoot or forefoot when striking the belt. Avoid slouching or holding onto the handrails, which can strain your body unnecessarily.

7. Cool down

After completing all three intervals, cool down by walking or jogging slowly for 5-10 minutes. Stretch your major muscle groups, focusing on your calves, hamstrings, quads, and hip flexors.

The Game Changer

The 12-3-30 treadmill workout may be just what you need to lose weight this year. So why not dedicate the next few months to it? When you look back, you’ll thank yourself for starting. Remember, gradually increase the duration, incline, or speed as your fitness improves. Don’t try to do too much too soon, as this can lead to burnout or injuries.

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