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MAF Training review – Part 6 When You Need MAF

My previous articles about the MAF Method discourage using the age-related formula for low heartrate training. But in this post I’m taking a more positive angle because there’s a reason people went to Phil Maffetone and he was able to help them. So while, I’m not a fan of the age-related formula, I am a fan of building good endurance which relates to what Maffetone refers to as MAF – Maximum Aerobic Function. While I’m not going to advocate using his formula, I am going to detail and explain the circumstances where a block of endurance training could be useful.

A parkrunner I know is a very capable runner yet, in a decade of running, his progress has been very limited. In fact, he’s barely knocked a minute off his parkrun time. When we first met he’d been running again for perhaps six months. He’d been a talented youngster, quit and now returned to running as he approached forty. It hadn’t taken much training to achieve a twenty minute parkrun yet in all the running since he has barely scraped under nineteen minutes. Despite training five days per week, six at one stage, he really hasn’t made much progress.

His years of running have been blighted by Achilles’ problems. Whenever he starts to train harder with speedwork his Achilles becomes sore and limits his running. He then backs off the pace until long after the Achilles has healed, only to restart the speedwork and go through the same issues. Until recently he was able to run a 19:30 parkrun at full effort but over the last year he’s developed a hamstring injury and is struggling to break twenty minutes. On the tougher local courses, he can’t even break twenty-one minutes!

If he could go to Phil Maffetone, I’m sure MAF would get him back to health and restructure his training to help him improve. I’d still argue against using the age-related MAF formula because he’s over fifty and training at 125 (further five beat reduction for recent injury) isn’t going to produce decent longterm results. Yet, as you’ll see in the next section, he’s clearly not getting the aerobic development Maffetone would encourage and is running around almost every day of the week at heart-rates which are too high.

A typical week’s training when you need MAF

He typically runs five days per week – three midweek, a parkrun on Saturday which is always a faster effort, a Sunday run which is his longest of the week while the Wednesday run tends to be slightly shorter. He gives himself two rest days which, being on Monday and Friday, space the week’s training out nicely. All in it’s not a bad training structure to follow. Here’s the heart-rate graphs from those five days of training.

I’ve put a yellow line to indicate where a heart-rate of 150 occurs and you can see that on every run he is reaching and surpassing it for a decent portion of the time. In fact, at parkrun the heart-rate reaches 170+ and most days he’ll be hitting the 160s at some stage of the running. He’s not just exceeding 150bpm but exceeding it significantly on almost every run.

I consider the overall amount of time spent running each week to be an issue. Totalling about 25 miles per week in 3hr 20mins it’s not enough for a distance runner. Of course everybody leads different lives and has different priorities so I can’t be too critical. Yet at less than an hour the Sunday run isn’t long enough and it should surely be possible to find more time for it. If he was an 800m runner, an hour might be long enough but he isn’t; he describes himself as a 5K / 10K runner. Apart from a couple of ten mile races and a half marathon; 10Ks have been the furthest distance raced in all these years. This overall lack of training volume is part of the problem.

The average pace for the week is 7:45/mile and the Wednesday run is the slowest at 8:11/mile. Given a parkrun time that is just breaking twenty minutes, Jack Daniels’ VDOT tables suggest Easy runs should be somewhere around 8:30/mile pace. So again, alongside the evidence of the high daily heart-rates, we’re getting an indication that there isn’t enough genuinely easy running taking place.

There’s two more problems these stats don’t reveal. On each of the training runs he stops to cross roads which give him one to three minutes recovery on any run. There’s over nine minutes of stops built into these runs. It may seem picky but anyone who has done distance training knows a break is refreshing. If you’re running anaerobically those breaks allow you to recharge the batteries and keep pushing (too) hard. Now you may argue it’s impossible not to stop but, with good timing and route choices it can be avoided. I often go weeks without needing to stop on any of my runs simply by running on roads with low levels of traffic, early in the morning and being flexible about when and where I cross roads. I will happily run an extra fifty paces up a road to let traffic die down before crossing it. But obviously do the safe thing.

The other unseen problem in these graphs is there’s some decent hills on the routes. He’s trying to maintain the same pace up and down them but that pushes the effort up which explain some of the higher heart-rates.

Graphing all those runs differently we can see the time spent in a MAF-HR zone of 130 or less; a middle zone of 131-150 which is usually safe for older runners to train at and a 150+ zone where the training effect is large but also takes time to recover from.

It’s clear he’s running hard five days per week with heart-rates hitting the 150+ mark. You would think the two rest days would be enough but they aren’t. What’s actually happening is the muscles are being trained anaerobically. The days after the rest days (Tuesday and Saturday) are faster runs because the muscles are refreshed but all that allows is for him to go out hard and reinforce the anaerobic training. There is no aerobic development. One of the benefits of day-in, day-out training is it leaves the legs somewhat fatigued to the point where they have to go slower and that helps the aerobic development.

The main consequences of this approach are that he’s getting injured and not improving.

What good training looks like

Injuries were the sort of thing Maffetone was happy to dive in and sort out. As I have stated repeatedly, I’m not a believer in the age-related formula but I am a believer in what Maffetone was trying to get his clients to do which is stay healthy and get faster by building an aerobic base through good endurance training.

My own training during this period saw me run nearly double the training our Needs MAF runner was managing. I was just shy of fifty miles taking 6hr 24mins yet we had the same average pace for the week at 7:45/mile. Despite all this extra mileage I’d been training every day for almost three years without illness or serious injury. While I picked up a couple of glute strains along the way (which came from trying too hard in speedwork) neither lasted more than a week and I was still able to run. While our parkrun times are similar, my base endurance is improving and I am positioning myself to go faster in the longterm.

You can see I run every day but only push harder on two days (Tuesday and Friday). There’s a few little glitches on my heart-rate monitor particularly Wednesday which highlights the problem of accuracy with heart-rate training but otherwise I’m comfortably well below 150HR on my recovery days. My Sunday long run sometimes scrapes into the red but the training effect I’m interested is in building endurance on those runs. Even a good ninety minute run is still only a hard, aerobic effort. Where the Needs MAF runner has to take two rest days every week, I’m getting out there and running on them too.

Another intriguing detail of our training weeks is that we accumulate the same amount of 150+ ‘red zone’ training time but my extra running accumulates time and fitness in the supporting zones while allowing the body to recover from the harder sessions. If I tried to run hard every day like he does, I’m sure I would be getting injured too.

We’re both fifty years old and Maffetone would like us to be doing all our training to a heart-rate of 130 or below. I don’t believe in that but I do total over an hour of my weekly running at this level and it’s usually in the first couple of miles of the runs while my body warms up. This is important – I’m listening to my body to get an indication of how it feels and whether I can push hard. Maffetone talks about doing warm-ups in his book but the people who think he’s only about low heart-rate training miss this.

On days following a harder effort I find my legs don’t want to do too much and it is a struggle to get the heart-rate up. My legs can be glycogen-depleted so I just jog along to aid recovery. If I tried, I could probably push to higher levels especially if I’d had a day off but I don’t try to push it every day and that was Maffetone’s message.

80-20 training

Much of Maffetone’s work occurred in the 80s and 90s when heart-rate monitors were still new. The science of exercise physiology has progressed a lot in recent years. What we now know, due to the work of Stephen Seiler, is that elite athletes tend to split their training into 80% below lactate threshold and 20% above it.

Throughout this post I’ve referenced a HR of 150bpm. Be careful – 150HR is not THE definitive value to use; it’s the data that was available to me. That the Needs MAF runner trains somewhere around this level most days shows it is probably somewhere around his own.

One hundred and fifty is close to where my lactate threshold heart-rate usually lies and I calculate I have a 76-24% split above and below it. That’s within the bounds of 80-20 training. On the other hand, the Needs MAF runner’s training split comes in at 54-46%. It begins to explain why he’s failing to make progress and getting injured when he starts to do even more intense work!

Arguably it may be wrong to use 150HR to split his training but it’s clear he’s training too hard every day because his body is letting him know through injuries and lack of progress. You can also see when he runs 30secs/mile slower on Wednesdays, he has lower heart-rate so it would be easy for him to include more genuinely easy-paced runs. Doing that, as Maffetone outlined is the key to staying healthy and injury-free.

Although I’ve been explaining all this using data you don’t need a heart-rate monitor to know whether your training is going well. Just a bit of common sense and listening to your body will tell you. When it creaks and groans it’s time to back off.


My six posts on MAF training are among the most detailed and honest articles about it on the internet and well worth reading. I’m trying to help runners get past the idea that training to a single number on a heart-rate monitor is the answer to all their problems. Good training involves scheduling the right mix of sessions at the right times. A block of endurance training like Maf suggests is just one part of what you need. My years of training and coaching allow me to know what to do and when to do it to help runners get fitter, faster and healthier. If you too would like me to help you then please contact me with details of your running and how you think I can help you.

MAF Training review – Part 2 My Experience

This post is the 2nd in a series of six. Other posts can be accessed from the Readables menu tab.

Today I continue my in-depth review of MAF training with a look back at how it went for me in the summer of 2014. In part 1 of this series, I explained most people promote the Maffetone Method as low heart-training, but it’s actually a holistic system including re-evaluating your diet by taking a two week break from refined carbohydrates. I too was in the heretic camp and went with the low heart-rate training only. I didn’t change my diet or try any of the other things Dr Phil Maffetone recommends, partly because if I gave up carbs I wouldn’t have anything left to eat. I read a copy of his book while I was doing the training and was trying to make sense of it as I was going along.


This wasn’t my first experience of low heart-rate training, that occurred over twenty-five years ago as I recounted in this post about John Douillard’s Body, Mind and Sport book. Using “Darth Vader” diaphragmatic nose-breathing, while running to a sub-130 heart-rate, I saw no success at getting faster or achieving the effortless flow state he promised but I kept trying. It was only when I got good at running through pace-based training that I began to see the low heart-rates promised by Douillard. But the idea of low heart-rate training stuck with me and somehow I read about Maffetone training and when the opportunity arose I decided to give it a dedicated shot.

My first two years of committed running (2011-13) saw me recording personal bests at all distances raced but something was missing which was stopping me from hitting the heights I hoped for. I didn’t quite know what it was but the combination of The Redgrave Paradox, a return from a winter virus and wanting to try new things led me to give MAF training a try.

The winter virus knocked my training back for two months and while, I’d missed the half marathon I was aiming for, I was still running capable of running twenty-one minutes at parkrun. With the virus over I began to bulk up training with four mile runs in the morning and another thirty minutes of barefoot running in the evening.

In early May I clocked forty-three minutes at Lymington 10K. A week later I jogged round Bournemouth parkrun in 25:43 with heart-rate averaging 141bpm but hitting a max of 155bpm. I’m not sure why but, that evening I decided to try MAF training. I was 42-years-old, the formula gave me 138bpm and in the past I’d always found my running felt very comfortable at this level. When I was building my first aerobic base three years earlier it was where my heart-rate naturally seemed to fall on easy runs.

Beginnings – May and June

I followed the MAF low HR regime religiously. The first Sunday long run was hellish because I picked a hilly route. I must have stopped and walked thirty times to keep my heart-rate down on the hills but I managed the twelve miles without going over the limit. It was slow at 10:24/mile with the fastest mile being 9:40 and the long uphill into Broadstone taking over eleven minutes. The following week was even slower but I stuck with it. Like all spiritual adepts there were times where I unintentionally fell off the pew and I did have one deliberation exception; at the end of some runs I would do a 150m sprint back to my house. It sent my heart-rate soaring and those moments are not included in any of the stats that follow.

In the first six weeks of training I ran, on average, for eight hours and fifteen minutes covering fifty-five miles yet only spending 1min35 above my MAF-HR of 138. I’m doubtful it’s possible to do any better than this. By the end of June I’d accumulated fifty hours of training but less than ten minutes of it exceeded MAF-HR.

Miles525647615656328
Total time8hr 18min8hr 44min7hr 18min9hr 23min8hr 48min8hr 36min49hr 34min
Above MAF-HR1min071min013min272min193 secs1min289min25

Most days I was running morning and evening yet what’s incredible is, while I was accumulating all this, I still took Fridays off as a rest day. I’m sure that helped parkrun to feel good on a Saturday morning. Monday to Thursday mornings were a shoed run with a barefoot run round a local field in the evening. At weekends, the evening run was shoed. Here’s a sample week from this period.

Time runMileageAvg paceTime above
MAF-HR
Monday00:41:414.5Morning run9:22 / mile
00:30:383.6Evening (barefoot)8:31 / mile
Tuesday00:41:064.5Morning run9:14 / mile7 seconds
00:31:033.6Evening (barefoot)8:38 / mile
Wednesday00:41:354.5Morning run9:21 / mile
00:30:273.6Evening (barefoot)8:27 / mile
Thursday00:43:104.5Morning run9:42 / mile8 seconds
00:30:523.6Evening (barefoot)8:34 / mile
Friday
 – 
Saturday00:31:154.5Bournemouth parkrun9:42 / mile11 seconds
00:34:393.6Evening recovery9:36 / mile
Sunday01:59:5111.7Morning long run10:16 / mile35 seconds
00:34:283.5Evening recovery9:50 / mile

Going further – July into August

In July I decided to change tack. I was still going to train to MAF-HR but the arrangement of my week would be different. The barefoot running had to come to an end. It was a long, hot summer and through June the ground began to harden up. It eventually became like running on concrete and my body simply couldn’t handle it. One thing I’ve haven’t yet been able to sort out in my running is not being a loud and noisy runner who hammers their feet into the ground. I know one guy who can run half marathons comfortably in a pair of Vibram Five Fingers on tarmac but I can’t do it for more than a few yards.

Part of my experimental mindset also wanted to see what would happen if I ran longer distances so rather than splitting my training day into two runs, I usually only ran once but much further.

Below is a training week which totalled 67+ miles and 10+ hours while only exceeding my MAF-HR for nine minutes. This particular week, my Bournemouth parkrun time scraped under twenty-seven minutes compared to the thirty-one minutes when I started. This was as fast as it ever got during MAF-HR training and it stabilised in the twenty-seven minute range in the following weeks.

Time runMileageAvg paceTime above
MAF-HR
Monday01:15:478.1Daily run9:18 / mile1min 23secs
Tuesday01:50:4411.7Daily run9:30 / mile4min 15secs
Wednesday01:14:228.2Daily run9:07 / mile12 seconds
Thursday01:52:0911.7Morning run9:37 / mile
00:36:374Evening recovery9:09 / mile12 seconds
Friday 
Saturday00:26:525.7Bournemouth parkrun8:39 / mile2min 15secs
00:32:383.8Evening recovery8:35 / mile
Sunday02:11:5914.1Long run9:22 / mile44secs

Many people who try low-HR training say they can’t run slowly. Part of it is they go off too fast but sometimes it’s their ego complaining. I never cared if people saw me running slowly. If anyone asked why I was jogging round at the back of parkrun I’d patiently explain the MAF training system with its focus on improving fat-burning over sugar-burning and then get on with doing my thing.

One of the reasons I stayed motivated was I knew the general approach of the elites is to do a block of ten weeks building their base. Sometimes they do this for longer but either way, the idea of replicating this helped me to overcome any doubt I was feeling when results weren’t showing up plus I had a reward in store to delay the gratification. When I’d completed three months of MAF training, I’d go to Poole parkrun and run all-out.

Even though I was completing Bournemouth parkrun 3-4 minutes faster, over those three months there was barely any improvement to my average weekly pace – it was always a few seconds faster or slower than 9:15/mile. The graph below shows this and the one notably slow week was when I totalled 77+ miles!

The reading I’d done suggested it would take three months for the aerobic base to be built. Not knowing better and not seeing any gradual improvement, I took it to be a timeframe where new speed or pace would appear at the end of it.

It therefore came as vindication when I ran Poole parkrun in 19:52 and I was very pleased to break twenty minutes. I’d been running twenty-one minutes before I started and I’d knocked a minute off with training. I now had the encouragement to continue on and see where this system could take me.

Peak experience – August into September

In the week following the parkrun my average pace improved to 8:51/mile – almost thirty seconds quicker. And it stayed there for the next three weeks. I thought I was finally beginning to see the promised gains and even put in occasional barefoot runs around the field again. These were proving quite efficient and I could run nine minutes with heart-rate averaging 115bpm. At my best I ran a sub-25 5K barefoot round the field without exceeding MAF-HR.

My Sunday long runs to Pamphill and back, which had originally been over ten minute miles, were now breaking nine minutes and I was even seeing a sub-8 mile on the downhill into Wimborne. The MAF training all seemed like it was going in the right direction.

Part of my year’s plan had been to do my UK Athletics coaching courses and I’d become a Leader in Running Fitness in May. The next level up, the Coach in Running Fitness course began with a full weekend in Exeter and meant I wasn’t going to be able to do my usual MAF training runs but I wasn’t too concerned as I figured a short rest would help. Over the two days we did many short practical sessions, both coaching and being coached by our partners but nothing extensive. We weren’t sent on one hour runs or anything, just technical drills, jogs and sprints and while my heart-rate was higher on the Sunday morning I thought nothing of it. I couldn’t get out of doing the practicals but I thought it would also be a test of MAF training’s effectiveness, no runner should have to be so perfect in their training if a system works.

Collapse – September into October

On the Monday morning I woke up … eventually. I’d slept for twelve hours, 10pm – 10am, and still felt exhausted. I played it safe and took the day off from running and resumed the next day. While the first couple of miles were ok, by the end of the run I was slowing my pace drastically to avoid breaking the MAF-HR.

Over a weekend I’d gone from being able to run over eight miles in 1hr10 to barely more than seven. In pace terms it had dropped by a minute per mile (8:38 to 9:40/mile pace). It clawed back slightly over the next four weeks but never back to where it had been. It was still an improvement over where it had been in June and July but not at the late August peak. I was still putting in the effort with weeks of 65, 63, 59 and 58 miles but the pace was often the wrong side of 9min/miles.

Enough – October into November and December

I was beginning to lose faith and needed to know where I was at, so in mid-October I went back to Poole parkrun. I’d run 19:52 nine weeks earlier but now I could only achieve 20:39. It had all fallen apart with one weekend of non-MAF training. I felt disheartened and ready to give up. I’d never truly seen the improvement that seems to be promised by low heart-rate training and I couldn’t see myself shuffling through months of my watch beeping at me.

I was scrabbling around for explanations and diving back into the Maffetone book I began to wonder if the increased heart-rates I was seeing were due to overtraining. It can be one of the signs and MAF’s recommendation for overtraining is to cut your training volume back. So this is what I did. All that happened was it became increasingly harder to run to MAF-HR off less and less training.

I was left wondering whether the previous winter’s virus had flared up again even though I otherwise felt fine. I took more and more rest days logging only 55-60 miles in each of November and December; mileages which had once been my weekly exercise had now become monthly. I was done with MAF training. I’d started it in May, shuffled around for months and not got anywhere closer to the best running I’d done in the preceding years. I felt like I was always waiting for it to come to fruition and it never did.

Looking back

Within this post, I’ve tried to sum up my training for people to understand what I experienced while avoiding getting bogged down in the details. Even now I feel it’s quite stat-heavy. Every run I did that summer is recorded in Garmin and on spreadsheets. So many of the runs are virtually identical in their splits, heart-rates and times that there’s little to be gained from reproducing them, a summation seems enough.

I’m split between saying MAF-training worked and saying it didn’t. Unfortunately I didn’t have an outright benchmark to compare between when I started training and the all-out August parkrun that clocked in at 19:52. I think it was an improvement but I’d been capable of running this sort of time in February before I got hit by a virus.


The first question mark is when you look at my average weekly pace over those first three months it doesn’t change. It’s always somewhere around 9:15/mile. It’s hard to make a perfect comparison because I changed routes from the beginning of July but whenever the opening miles were along the same paths, the splits were very similar. It suggests I wasn’t getting any improvement from the MAF training.

It was after the 19:52 Poole parkrun that things picked up. The pace of my Sunday runs were notably quicker than they’d been in May when I was trudging up hills taking over eleven minutes for a mile.

The trouble is the fast parkrun seems to have been the trigger for this improvement and that isn’t part of the MAF training. The whole theory of MAF training is that you will get quicker simply by running below MAF-HR. [It should be pointed out the book allows you to add in some Anaerobic Intervals from time to time, but if you follow what the Youtubers say it’s simply about low HR training. Once you start mixing aerobic and anaerobic work you’re heading back towards conventional training methods.]


The second big question mark about my MAF training is what happened after my run coaching course. I went backwards and never reached the same heights of the 19:52 parkrun again. If you look at it over the whole five months of training there was no improvement – I was capable of running 21-mins at parkrun before, I ran 20:39 after.


I believe I adhered to MAF training as well as anyone could or should be expected to. I logged hundreds of miles in over 200 hours of training at slow paces. In almost six months I only totalled 4½ hours above a heart-rate of 138bpm and that includes two 20-minute parkruns where it was averaging high 160s. The graph below shows the time running with the yellow blocks representing the small percentage of time spent in excess of my MAF-HR. You can barely see any yellow in the first six weeks which reflects how well I was following the system.

What my stats don’t include are the occasional 30-second sprints I did at the end of training runs two or three times each week, or what occurred on my run coaching course. If this were a true scientific experiment they would be question marks against the validity of what I did, but with over 98% of my training as MAF expects I don’t believe they should be the difference maker to its effectiveness.

The biggest disappointment of having followed the MAF training system for all those months is that any gains I did make, didn’t last. I ran 1,345 miles to try and build the fat-burning system as Phil Maffetone suggests. By the time I ran parkrun on Christmas Day I was only able to achieve 21:45 with notably higher heart-rates than they’d been in August. Where I’d averaged 165 then, now I averaged 169. Where the maximum had been 174, now it was 181. In a matter of months, I’d gotten slower and my fat-burning had got worse. While I trained less in November and December, I’d have hoped the conditioning would last for longer.

But perhaps more importantly, whether I think my experiment proved MAF training works or not, here’s how I felt about it.

My overriding memory is of how much I grew to hate it,

I grew to dread the watch beeping at me to slow down.

Many hours were spent each week trudging along at paces close to 10min/mile. There was never any chance to break out and run fast, I was always trudging along barely lifting my knees or opening my stride. I was always waiting for the watch to beep. Not just a single tone but an irritating diddle-iddle-eee like a demented doorbell from the Seventies.

I enjoyed the evening runs much more but that was more down to the novelty of running barefoot laps round a field and feeling the ground fly beneath my feet. The lack of footwear reduced the energy-cost of running and my heart-rate stayed lower so I got to run faster.

But too many hours were spent trudging along in the mornings; automatically slowing down to trudge up hills; forever aware and vigilant for the beep of the watch ordering me to slow down.

While I was highly motivated to give MAF training a good shot, grasping for any sign of improvement, the slow pace meant my legs barely got out of first gear and I was repeatedly trashing the same muscles day after day. Running so many miles left them feeling hollow and lacking spring, and the lack of variety just made it unenjoyable. The only redeeming factor was that this all took place in the warm of the summer months. I’m doubtful I could have stuck with it through a cold, windy, rainy winter.

The one bright spot was the 19:52 parkrun at Poole and that was it. I believe you need more intrinsic feedback and enjoyment when you’re training hard to stay motivated through the tough times. If, for some reason, you aren’t getting that feedback then this is where having a good coach helps out. They will reassure you that you’re on track to achieve what you’re aiming for. They find ways to say “Don’t worry, it’s going to work out”, to point out any successes you haven’t noticed, or explain why the slump you’re experiencing is normal. In this respect, my years of coaching enabled me to self-coach and keep giving positive messages and reinforcement.


Knowing how my running improved in the years after, I realise I’d never use MAF training again. Its monotony and the age-related MAF-HR meant it didn’t work for me.  Becoming a slave to the beep of a watch and heart-rate monitor sucked the enthusiasm out of me.

I know, as I can show to anyone I coach, there are better ways to train. Endurance miles are an important part of the equation but not the only one. It’s possible to mix up bouts of fast and slow running in ways that allow you to get the best out of yourself and see intermediate improvement while the training comes together.

In part 3, I’ll talk further about what I believe the pros and cons of the MAF training system are. When it can work, what you can learn from it and what the issues are.