Social media can be a bit of a goldmine for fitness content – can be. It doesn’t always work out so well. There will always be somebody looking to sell you snake oil, somebody more concerned with their own image than the quality of their advice, somebody well-meaning who is actually not as well versed in fitness expertise as they think.

However, once in a while, a real treasure can be unsurfaced. From YouTube HIIT and yoga videos to Instagram fitness transformation stories, there is a lot of useful, inspiring stuff out there. There are a lot of workouts and fitness methods circulating the wonder-web that can be really quite useful.

The 12–3–30 workout, courtesy of social media influencer Lauren Giraldo, has been doing the rounds of late. She originally put it up on YouTube in 2019, but a viral TikTok video from November last year has been seen almost 12 million times, cementing its popularity.

Giraldo is no fitness buff, nor does she claim to be. She isn’t a runner, certainly. However, she seems to have caught the public’s attention with her 12–3–30 workout, a treadmill routine that she claims is accessible and practical for all. She stumbled across it almost by accident, seemingly.

‘My gym’s treadmill had 12 incline as the max,’ she says. ‘Three miles per hour felt about right, and my grandma had always told me that 30 minutes of exercise a day was all you needed. That’s how the combination started.’

This is the basis of the workout. Everything else just followed naturally.

Though three miles per hour may not sound like much – realistically, it’s an average to fast walking pace – walking on an incline on a treadmill is surprisingly hard work. Especially when that incline is as high as 12. Doing so for 30 minutes is no joke. It certainly isn’t a walk in the park (pun intended.)

However, as a fitness professional, I have to ask whether it is all it’s cracked up to be. Is it effective, is it safe, is it accessible, is it useful, is it efficient? Or is it simply one more fitness fad that has caught the world’s attention for the moment without having any real backing behind it?

Let’s take a look and see.

What is the 12–3–30 workout?

What is the 12 – 3 – 30 workout?

The 12–3–30 workout is a form of steady state cardiovascular exercise performed on a treadmill. To make it a 12 – 3 – 30 workout, three settings on the treadmill need to be adhered to. These are:

Incline: 12

Speed: 3 mph

Time: 30 minutes

This is it. Simply walk at 3mph for half an hour, at an incline of 12. Giraldo claims she does this five times per week and credits it with an amazing weight loss of 30 lbs (around 13-14 kg). She also claims that the physical benefits were just the start – the mental changes were more significant. It inspired her to exercise and to keep at it, she felt very accomplished by sticking to it, she experienced all the positive mental health benefits inherent to exercise, and the ‘me’ time experienced by this kind of steady-state cardio can be really quite profound.

So far, so good. There is no doubt that a fast bit of uphill walking will burn up a fair few calories. As a caloric deficit is the main ingredient for weight loss, the 12–3–30 workout should in theory be a great weight loss aid. It certainly seems to work for Giraldo.

There is more to it than this, however. As mentioned above, Giraldo is no fitness buff or exercise guru. She isn’t an athlete, and actually used to feel quite uncomfortable setting foot inside a gym. This is not uncommon – intimidation and a sense of not knowing what to do and not feeling comfortable are a couple of the leading reasons that many skip the gym entirely. The 12–3–30 workout grounded her, let her know what she was to be doing, was hard yet manageable, and has kept her going back.

If you are worried about going to the gym and decide to try the 12–3–30 workout, and find that it works, that it helps you get over your anxiety and stick to a fitness regime, it will be a great success. More power to it.

Nor do you have to make a complete success of it the first time you try. Simply stepping onto the treadmill can be a success for some people. Finishing the routine can come later. In fact, Giraldo herself couldn’t finish it the first time she tried. At first, she needed to take a break or two throughout, having to work up to a solid thirty-minute stretch gradually.

Walking as a Stressor

Walking as a Stressor

In fact, it’s not recommended that you jump straight into the 12–3–30 workout if you’re new to fitness. It’s more intense that you may think walking would be, so taking it slowly and incorporating plenty of recovery days at the beginning is wise. Adding an incline adds stress to the muscles, particular the quadriceps and glutes, so it is tough.

Your lower back, hamstrings, knees, Achilles tendons and plantar fascia will all be involved with this kind of exercise, and they are all common injury hotspots for many people. Incline walking, especially at extreme inclines like this, can put stress on these regions. Moving solely in the sagittal plane, as this kind of exercise does, can lead to an increased injury risk over time. You risk aggravating these body parts and potentially doing yourself some real harm if you take on too much, too quickly.

Try performing it every other day, or even three days per week. Add in sessions over time as you adapt, but only when you feel comfortable. Otherwise, the risk to reward ratio may be skewed unfavourably.

Alternatively, try changing it to a 6–3–30 plan. Still walk at 3 mph, still for half an hour, but at an incline of 6. Then take it up to 7 after a few sessions, then 8, and so forth until you get to 12. Let your body adapt to it.

Problems With the 12–3–30 Workout

Problems With the 12 – 3 – 30 Workout

This brings us onto some of the issues with the 12–3–30 workout. Working solely through the sagittal plane is one of them. In layman’s terms, this simply means moving front to back. Moving solely in one plane of motion can lead to an increased risk in injury and muscular imbalance over time. Our bodies need to move through all planes of motion, meaning that we need to raise up and down, twist, move side to side, and jump. This will create the stability and balance we need to not simply overstress one single joint or muscle group, and to create a well-rounded, mobile physique.

Simply performing the 12–3–30 workout five times per week will be very limiting and potentially risky over time.

The 12–3–30 is restrictive in other ways, too. Though, as above, you can adjust it for different incline levels, and even speed and duration, this takes it away from being ‘The 12–3–30 Workout.’ They are also small adjustments – the basic theory will be the same. You need scope for listening to your body and properly adapting, which simply won’t happen with this kind of protocol.

The constancy of pace is an issue, too. It is quite hard to jump in at an incline of 12 without warming up and perhaps performing some mobility at first. It may also be more effective to oscillate intensity, bringing it up and down over the course of half an hour.

Again, it’s limiting.

There is also perhaps little room for progressive overload, one of the fundamental principles of fitness training. Under progressive overload, we place our bodies under increasing amounts of stress as they adapt, so that we are always progressing and adapting, always improving. To achieve this, many fitness professionals use the FITT principle.

FITT stands for:

  • Frequency
  • Intensity
  • Time
  • Type

If you manipulate any one of these to add workload, you will likely be eliciting progressive overload. For instance, in a weight training context, you could go from 3 sessions per week to 4, thus increasing frequency. You could lift heavier weight or spend less time resting, thus increasing intensity. You could spend more time lifting per session. Or you could switch around, changing from Strongman training to Olympic lifting to calisthenics, with six months to a year devoted to each.

Doing any of the above will make sure that your body consistently has new stimulus, which is needed for adaptation.

Many of these are lacking in the 12–3–30 workout. Frequency can be adapted. Instead of doing the routine twice per week, do it three or four times. Intensity may be adaptable, if you invest in some wrist or ankle weights, or something similar, though this still doesn’t give much scope for long term adaptation, and speed and incline are fixed. Time and type are fixed – it is 30 minutes walking each and every time.

Once more, it is a very limiting program.

The argument could be made that it’s better than nothing. I personally hate this argument, however, as it ignores opportunity costs. It assumes that the only options here are to do the 12–3–30 workout or to do nothing, in which case the 12–3–30 workout wins hands down. But these are far from the only options. If you spend your exercise time doing the 12–3–30 workout, you won’t spend it doing something more productive – this is an opportunity cost.

Furthermore, walking is amongst my favourite styles of exercise going. I spend at least an hour doing it every day, usually two or more. With my dog, in parkland and woods. This is far better than getting on a treadmill. If you want to get some good quality steady state exercise in and fear the gym, do this.

There is far more to walking than simply the muscles moved and calories burned. The benefits of walking involve the mindfulness and meditation of being out in nature, lost in your own thoughts, surrounded by the vibrancy of life. The natural variation in any landscape will give you variable inclines, thus taxing your body in different and far more naturalistic ways.

The 12–3–30 sounds OK. It may even be good, at least for some people. But there are far better ways to achieve similar results.