MAF low heart rate training has many benefits to become a stronger, healthier and happier athlete. This is one of the main attributions of how I improved from a 4:11 hour marathon to a 2:44 Boston Marathon, while making the training process much more enjoyable.
Two comments I often hear about MAF training are:
“I have to run so slow, it is very frustrating, I even have to take walk breaks to keep my heart rate below the calculated MAF threshold level”
“I have been doing MAF training for several weeks or months and I’m not getting any faster. I feel I am getting slower and I’m paranoid that my fitness is going down.”
Before we dive into answering both comments, let’s take a step back and talk about the high level concept of the MAF method. Developed by Dr. Phil Maffetone, the concept is focused on 3 elements: exercise, nutrition and stress. The method improves the function of the aerobic system, the fat-burning engine responsible for fueling all of the body’s needs.
In line with Dr. Maffetone’s thinking, I also strongly believe in this holistic approach to training. Making sure all elements in your life are in line and not just focusing on the running part. The right nutrition and lowering stress levels are other important components that will be discussed in further detail below.
One way to find your optimal heart rate for aerobic training, the max aerobic heart rate, is the 180 formula formulated by Dr. Phil Maffetone. Once you know this number, you train for at least 3 months all your runs and other workouts at or below this heart rate to build a strong aerobic base. You teach your body to use more body fat for energy than previously done, so you become a better fat burning. This means, almost all athletes who start out with MAF training have to slow down their training pace to a slower jog or walk to stay at or below their MAF HR.
One note here, although the 180 formula has a high accuracy for most athletes, treadmill testing is still ideal. Although this is not easily accessible for everyone and relatively expensive.
The benefits of MAF training:
With this MAF training approach, you burn more body fat, increase your energy and brain function, limit the risks or injuries and disease, build greater endurance, strength, speed and physical fitness.
On a monthly basis you can take a MAF test on a running track, to measure your aerobic progress. You warm up for 15 – 20 minutes, then run on a track for 5 miles (or 8 km) and write down your splits. Here is an example of an athlete with with aerobic progress, notice every month the athlete becomes faster at the same heart rate:
Doing a MAF test on a monthly basis, is a long enough interval to see differences in tests. Many athletes get so obsessed by analytics that they measure their progress on much more frequent intervals, which can negatively impact their mindset, especially if no progress, or even short term regress shows up as your body adjusts.
The most common reasons for athletes not to progress with MAF training:
- Poor fat-burning
- Going over MAF HR too often or choosing too high MAF HR
- Poor nutrition and disordered eating
- Muscle imbalance impairing gait and economy
- High levels of stress
- Limited or no warm up and cool down
Let’s discuss these in detail and what to do about these.
If you have trained for a period of time with too much high-intensity, you are in a constant fight-or-flight response mode, a physiological reaction that occurs in response to a perceived harmful event, attack, or threat to survival. In this state, you are never able to fully relax. In the short term, in this stressed state, your performance can be greater than what is healthy.
When you slow your training intensity, your body is going back to a more natural state, no longer having to compromise in survival mode, fighting for its life. Because of this transition, your body is no longer willing and able to produce the same level of output as in a stressed state. First you need to get this stress out of your body to get a chance to develop the aerobic system.
This repairing of damage can take longer for some athletes than for others. Patience, consistency and a positive mindset are important here. Rest, recovery and enough sleep are also very important elements to reduce your stress and improve in your training.
Even at a MAF pace, athletes can overtrain by adding too much training volume and not enough recovery. Especially for athletes who have previously trained at a high intensity, their bodies need to have a chance to rest and recover properly. If you want to improve aerobically, take a rest day sometimes, your body and mind needs it. I see too many athletes not taking rest days, while they absolutely should.
Here is an example of I comment I read today:
Athlete 1, let’s call him Peter: “I have been doing the maf training plan for 3 months. Running 8 miles a day, long run 16 miles, no days off all miles under 135 heart rate. I am not seeing any results any suggestions – a 47 year old runner”
Athlete 2, let’s call him James: James started with MAF training, didn’t see improvements within 7 days and mentioned to me: “I’m paranoid that my fitness is going down”. When reviewing his Strava, it showed for the last 18 days he ran every day, for an average of 1 hour 35 per day! No rest days. In the past 7 days he ran 1 hour 43 minutes a day, all in 1 go, that’s more than 12 hours of running in a week. Even during my peak marathon training weeks that I ramp up volume over many months, I don’t get to this type of training volume.
My rule is gradually build up your volume, add no more than 10% in volume increase a week, every 4th week a step back week of at least 30% in training volume.
In these 2 runner examples of Peter and James, I’d highly recommend to cut back training volume significantly and add rest days. For example, start out by running every other day, do a good warm up of 15 minutes, run at MAF for 30 minutes, and cool down for 15 minutes. Slowly add some more training volume over time as your body can handle it.
Eventually, if you build up your volume and have enough time available to train, split up some of your 2 hour runs into two shorter runs in 1 day. This can help recovery as well, while increasing training volume.
Remember, it’s a marathon, not a sprint. Training to become a stronger, healthier, happier athlete is a long term holistic approach, not a quick fix.
2. Poor fat-burning
This goes hand in hand with overtraining and nutrition. If you have overtrained and had poor nutrition for a while, it will take your body time to repair the damage before being able to improve. Your body will have to get used to burning body fat for energy efficiently.
Another note about overtraining and poor fat burning, I’ve come across several athletes who do a lot of cross training and strength training. All these workouts can add additional stress. During the MAF base building, it’s highly recommended to keep your heart rate at or below MAF. At this pace, either cut out all strength training, or limit the duration and intensity significantly.
3. Going over MAF HR too often or choosing too high MAF HR
When using the MAF 180 formula guidelines, as provided by Dr. Phil Maffetone, you subtract your age from 180 and adjust this number accordingly to your profile. Be honest with yourself here about which fitness and health profile category fits best for you.
Dr. Phil Maffetone developed his original 180 formula 35 years ago. In October 2018 he updated this formula with 2 additional health factors, based on changes in the world.
An addition to minus 5 beats for overfat athletes
“Excess body fat poses many possible health and fitness problems, and is often the reason people don’t get faster at the same HR. Your waist should be less than half your height — if it’s not, subtract 5. “
FYI – estimates of U.S. adults being overfat: Males up to 92%; Females up to 83%!!!
An addition to minus 10 beats for chronic overtraining
“These individuals, often athletes who are chronically burned out, those who have had a nervous breakdown or are otherwise chronically stressed, are really seriously unhealthy too. Many athletes are not progressing, continue to have poor performances, various injuries, often because they are chronically overtrained and don’t realize or can’t accept it. When people experience how easy or slow it is to work out at this HR, they are dismayed, thinking it will be like this forever. It won’t … ” Read full article The 180 Review on Dr. Phil Maffetone’s website.
I have come across many athletes who add +5 beats while they shouldn’t have. +5 beats should only be added if:
- You have been training for more than two years without any of the problems described. This includes being without physical, biochemical or mental-emotional injury.
- You have made progress in athletic competition.
- You are not overfat as indicated by the waist-to-height ratio.
- Your MAF Test is improving.
Whenever you are in doubt, be conservative and pick the lower HR number. More specific details about this can be found in the original 180 Formula article with 1000+ comments on Dr. Phil Maffetone’s website.
The 180 MAF formula will give you a HR that you should not exceed during the base building phase. Let’s say this number is 135 beats per minutes. Your training zone becomes 125 to 135 beats per minute (10 beats below to MAF HR). I recommend setting your GPS watch alarm at 135, so every time your HR goes over 135, you’ll start to walk or slow down your pace. Even if you go a few beats over your MAF pace, some people can already experience slightly additional stress responses, which should be avoided during the MAF base building period of at least 3 to 6+ months.
On hot and humid days there is weather stress on your body and you should also keep your HR at or below MAF during the base building phase.
“I have to run (and walk) so slow, it is very frustrating”
Initially I also struggled to slow down in training, however I found ways to turn my frustrations into excitement. Here is a detailed article I previously wrote about this: Overcoming frustrations with MAF low heart rate training.
4. Poor nutrition and disordered eating
One of your key goals with low heart rate training is to improve your fat burning abilities. If you train very well, but you eat a lot of junk processed food and refined sugars, your aerobic progress will be limited. Eating healthy unprocessed meals will burn more body fat for energy which helps develop your aerobic system.
I usually eat 4 to 5 meals and snacks a day: breakfast, early lunch, afternoon snack, dinner, evening snack. I eat a pretty balanced combination of fats, proteins, fiber, some unprocessed carbohydrates, vitamins and minerals. This way your body does not crave sugars for energy fuel. This diet in combination with proper Aerobic HR training significantly improves your metabolic efficiency.
There are many athletes I come across who experiment with intermittent fasting, multi day fasts, high states of ketosis etc. Without going into a long essay, during a MAF base building phase I don’t think running fasted speeds up your aerobic development.
Last week I was approached by a woman in her forties who was not seeing any aerobic progress. When reviewing her nutrition, she turns out to be experimenting with 18 hour fasts, while on on a vegetarian keto diet, so high fat, low carb, no meat. My first reaction was to stop the fasting experiments and eating more frequently.
Also, for me personally after years of experimenting, I don’t perform optimal when I cut my carbs back too low. Therefore on higher training volume periods, I eat some more nuts, beans, etc.
5. Muscle imbalance impairing gait and running economy.
Muscle imbalances happen when one set of muscles have a different strength or size compared to an opposing group of muscles. If one muscle is weak and the other is overactive, it pulls your body into bad posture.
Four ways to improve running economy:
- Using a standing desk vs sitting behind a desk for extended periods of time. I made this switch in 2015 and this was a game changer for me, my back and legs felt much stronger after introducing this. Make sure to build this up slowly, starting with short periods of standing, increasing gradually.
- Improving your foot function by spending more time barefoot, walking around your home or office. Also, going for short jogs on the beach, local parks, etc can help. Don’t overdo this, slowly easy into it.
- Using the right running shoes for you without too much support. Also, making sure your running shoes are the right size. Running shoes should feel a bit bigger than your casual shoes. You should have about 1 thumb’s width of room between the end of your longest toe and the front of the shoe. This could mean you’ll have to buy a larger size running shoe than you’re used to in your regular shoes, in order to get the fit you need.
- Performing your workouts slower allows your body to go through the proper motions. Over time as your aerobic system develops, your brain will perform faster with more economy.
- Dr. Phil Maffetone wrote several great detailed articles on these topics on his website: Muscle Imbalance part 1, Muscle Imbalance part 2 and Gait part 1 and Gait part 2.
6. High levels of stress
Stress is a very important factor when looking at a holistic approach of training and racing. Too much stress will block your aerobic development and reduce your fat burning. There are many ways to reduce your stress. A few of my favorites:
Meditation to lower your stress
Daily meditation has made a huge impact in my life and I strongly believe that meditation has made me a better runner. My approach to running is holistic, making sure that all elements of my life are in sync. Meditation plays an important role in this and comes with many benefits: it increases happiness, benefits cardiovascular and immune health, changes our sense of self, reduces stress, improves concentration, and encourages a healthy lifestyle. Two great resources to get started with meditation are the Calm App that can be downloaded in the app store and also The Open Heart Project by my friend Susan Piver. I interviewed her previously on my podcast titled: “Meditation and Mindful Running with Susan Piver“.
Limiting caffeine intake
People’s sensitivity to caffeine can vary greatly, however high does of caffeine can increase anxiety.
Writing down what you are stressed about, or writing down what you are grateful for. I use The 5 Minute Journal, more about this can be found in My Morning Routine post.
Spend time with friends and family
Having strong social ties is one of the common longevity lessons in the Blue Zones. This may help get through stressful times and lower your risk of anxiety.
Sleep / rest / recover
One of the most overlooked part of training for athletes is getting enough rest to recover properly. Many athletes don’t sleep and rest enough, so it becomes harder for your body to recover from workouts and improve in your training. Healthy sleep is about seven to nine hours of uninterrupted sleep. For athletes running 50–60 miles per week, 7 hours of sleep is probably not enough. Top athletes training 20+ hours a week will need closer to 9 hours to get the recovery. We get more training benefits from the recovery phase than the actual training. We need that recovery to allow our body to naturally progress.
7. Limited or no warm up and cool down
If you don’t allow your body to warm up properly, your core muscles are going to contract, heart rate is going to increase rapidly and your legs will get flooded with blood. This will bring additional stress to your organs, wear you down more and can even cause a shock reaction in your body.
A proper warm up of at least 15 minutes is important, to make sure your body and mind are ready for action. By warming up slowly, some of your blood has an opportunity to leave the internal organs and go to your muscles.
One way to warm up, is to start with a 5 minute walk, yes this alone will start numerous processes in your body. From a walk, start a slow jog, gradually picking up your pace over the next 10 – 15 minutes until you hit your MAF HR. I have personally noticed significant differences in MAF test results when I do a slow gradual warm up, vs running too fast too soon.
Cool downs are an important part of any workout, in particular speedwork. After a workout, your blood contains relative large quantities of CO2 and other by products of exercise. The cool downs allow for an effective recovery. If you don’t cool down, the “bad blood” stays in your body longer and it take much longer to recover.
For a cool down, you can reverse the warm up described early. So slowing your pace gradually over a period of 10 minutes, ending with a 5 minute walk.
That covered the 7 common reasons for non responsive athletes. One other important topic to cover.
Speedwork is an important part of MAF training
After several months of aerobic base training, you might notice from your MAF test that your aerobic progress starts to slow down, flatten out or even regress. First find out if this regress is caused by an upcoming illness, cold, added stress, poor sleep, or poor nutrition. If that is not the case, you can add some speedwork to your training schedule.
Initially you can add 15 to 30 minutes of intervals, once a week, 4 weeks in a row. I enjoy 800 meters or 1600 meters on a running track, or fartleg workouts on a hilly trail.
After about 4 weeks of intervals, you can re-evaluate how you feel. It’s important to stay healthy while finding out how much anaerobic training you can handle, without increasing your stress levels too much.
Typically I go back to aerobic runs only for several weeks, before doing more intervals or I might add some occasional faster group runs. Remember, you really don’t need much speedwork to become a faster runner over an extended period of time. If your body feels strong, you can add a second interval session per week, however use caution with this and listen well to the signals of your body.
If you’re overtrained, injured, or sick, it is important to train only at or below your MAF heart rate until you are healthy. This duration is different per athlete, this can take even more than 6 months.
There are many benefits to a MAF training approach to become a stronger, healthier and happier athlete. Reducing the risk of injuries and disease alone, can make a huge different in the long term progress for athletes. The increase in energy and brain function helps tremendously during training cycles. The greater endurance and physical fitness will be beneficial for all athletes, in particular those at the latest stages of an endurance event, like mile 20 / 32 km of a marathon!
Athletes should naturally progress and become faster over several months during the base building period, when training aerobically. For non-responsive athletes, common causes are overtraining, high levels of stress, poor running economy, disordered eating and limited warm ups / cool downs. These causes should be taken seriously for the long term health of every athlete.
If you have any questions at all, please let me know in the comments below and I’ll do my best to respond. Also, make sure to join our Extramilest Facebook with many likeminded athletes from around the world sharing experiences and supporting each other.
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