Hadd’s Approach To Distance Training: Frequently Asked Questions

[This is a first draft for people on the Hadd thread to add to, comment on and edit. Please don’t use for any other purpose at the moment.]
Disclaimer: This article tries to explain some of the practicalities of John Hadd’s approach to base training from what’s published on the web and what some fetchies have tried out. All the usual rules apply. Go to see a doctor before starting any fitness program, don’t expect miracles from any training and apply common sense and caution when it comes to illness and injuries. Oh, and Hadd says he wouldn’t recommend this training for under-18s.

So what’s this all about?

A few years ago a coach called John Hadd was posting on the Letsrun message board about his approach to training. A number of fetchies have followed this training to some great success, particularly at marathon distance. However because the training was described in lots of message board posts it doesn’t read well and it also contained lots of discussion on the physiology of rats and the like, so can also seem a bit technical and convoluted, hence this attempt to try to simplify.

What’s Hadd’s big idea then?

Hadd’s basic idea was that for a distance runner to perform to their best ability (squeeze as much toothpaste out of tube as possible is the analogy he uses) he or she needs to first develop a strong aerobic base. Many runners fail to do this either because they don’t run sufficient mileage or because the mileage they do is run too fast and so the muscles don’t have the correct adaptation. By training at the key aerobic training paces, and therefore developing the muscles correctly, a runner will improve their ability to race at pace over all distances from 5k upwards.
According to Hadd, muscles with better aerobic capacity accumulate less lactate which is why increasing the aerobic base makes you faster at all distances, not just those at distances like the marathon which are 99% aerobic. In addition to having a good aerobic base the other key to running faster at longer distances is to raise the Lactate Threshold (LT) pace, by training the muscles so than can maintain a higher power output for longer.

How does he suggest I build aerobic base?

There’s no great magic to building aerobic base. It just involves lots of controlled aerobic training. For Hadd this means running at a HR about 50 bpm below Maximum Heart Rate (HRmax) or in the range 70-75% of HRmax. For example for a runner with a HRmax of 193 bpm, 75% HRmax is 145bpm so the easy training needs to be at or below that level. This is the running intensity for all but a couple of the runs per week and this intensity does not change through the base phase.

And how do I move the LT pace?

To move your LT you must work below (slower than) the pace at which your LT currently turns. Therefore Hadd proposes a way of determining a HR/pace below current LT (but above the low aerobic conditioning pace). He suggests two long runs of an hour/ 10 miles at this HR per week as a way to move LT during the base phase. These runs are termed sub LT HR runs. The initial pace when starting Hadd training is determined as roughly 35-40bpm below HRmax or at 80% HRmax. However gradually over the base phase this sub LT HR will rise. When at this HR a runner can run for 10 miles with no noticeable HR drift or drop in pace over the 10 miles, then this HR is clearly below LT HR – because there is no apparent increase in lactate that is slowing the runner down. At this point the HR for the sub LT HR runs should be raised by a few bpm, no more than 5. Over time the HR at which it is possible to run comfortably without accumulation of lactate will increase. Hadd reckons the limit on this increase is that it is unlikely that a runner can sustain a HR of less than 15-20bpm below HRmax over a marathon. In other words a well trained runner according to Hadd is unlikely to be able maintain a marathon HR more than 90% HRmax and 87% HRmax may be a more reasonable estimate. (He estimates that Paula Radcliffe was running at 92% HRmax when she ran her 2.15 marathon but it’s not clear on what basis.)

Ok, how do I start in practice?

First, you need to get yourself a Heart Rate Monitor (HRM) - a bog standard one will do but one with a GPS or footpod to measure approximate distances is nice to have.
Second, you need to do a Maximum Heart Rate (HRmax) test. This can be done by doing a couple of flat out efforts at 800 and 400 metres, or by running a few intensive hill repeats. You take the maximum heart rate reading in this session as your HRmax. It important you’re doing these at full effort so that you get a measure of your maximum that you can be confident in – doesn’t matter within 2-3 beats but shouldn’t be further than that out – because the HRmax determines the HR intensities of your runs.
Third, Hadd suggests doing a 5x2400m test. This involves, on a windless day when you are well rested, running 6 laps of a track (or an accurately measured 1.5 miles on a flat traffic free loop if you don’t have access to a track) at 5 different HRs. Starting with a low aerobic conditioning HR (e.g 140bpm for HRmax of 193) and adding 10bpm for each set of 6 laps (1.5 mile). So you:
Run 2400m at a steady 140 HR (Stop 90 secs and record time)
Run 2400m at a steady 150 HR (Stop 90 secs and record time)
Run 2400m at a steady 160 HR (Stop 90 secs and record time)
Run 2400m at a steady 170 HR (Stop 90 secs and record time)
Run 2400m at a steady 180 HR (Stop 90 secs and record time)
At all times, adjust the running pace to maintain a stable HR. On each new stage slowly edge the HR up (it is ok if the HR takes the first 600-800m to reach target level), then simply maintain HR. DO NOT start fast and have to slow to maintain target HR.
Fourth, you need use your HRmax to calculate the HRs for easy running and initial LT HR runs. You can calculate these from the rules described above and there are a number of examples on pages 23-25 of Hadd’s Approach to Distance Training document linked below.
Five, away you go.

How much do I run?

There are no fixed rules on this. A typical week may involve an hour of running each day with a two hour run at the weekend. Of these runs all but two will be at easy, low aerobic conditioning HRs. The other two are at sub LT HR and should be spaced during the week to allow recovery.

Do I need to do the 5x2400m tests?

No, but many people find them helpful. It’s often a good idea to do one fairly early on when you start Hadd training as a way of getting an idea of your pace/effort at different Heart Rates. You can then repeat every few weeks to check on your progress if you like, but you’ll get a good idea of progress from comparing your runs at equivalent HRs over time anyway.

At 70% of HRmax I am walking/shuffling, how is this going to help?

Lots of people find the pace at 70% of HRmax very slow to start with. Hadd recommends training at 75% of HRmax, or no slower than 3 mins per mile slower than your 5k pace, if 70% HRmax is too slow. As you adapt over time you’ll find that you’ll be able to maintain a faster, more comfortable pace when running at 70% HRmax.

Should I use the percentage of HRmax or Working Heart Rate (WHR) as Karvonen calculates?

Hadd bases his training HRs on HRmax rather than WHR. Using the same percentage ranges to set pace but of as a percentage of WHR will give you HRs, and training intensities, that are too high.

When I read Daniels, or Pfitzinger and Douglas, they tell me to run LT or Tempo runs faster than marathon pace, why does Hadd tell me to run these slower than marathon pace? And who is right?

Hadd's approach is that running for fairly long times/distances below LT HR (and below likely marathon HR) while gradually over the weeks/months raising the HR at which you do these runs is the best way to achieve an increase in the pace you can sustain over long distances. Daniels and P&D typically recommend tempo runs that are closer to 10k or Half Marathon pace but for shorter duration/distance. In the Letsrun thread linked below Hadd points to a review article on endurance training which basically says that there is very little scientific testing of which of these - or any other approach works. The science doesn’t tell us which is correct, but Hadd clearly believes his approach delivers results.

Does this work for men and women alike?

Yes, Hadd says it works well for both men and women (he cites a 2.27 marathon time for a man he coaches and shows the HR stats for a 2.40 marathon for a woman he is coaching, so I believe him)

Do I have to train to HR can’t I just take my training pace from the 5x2400m tests?

The pace for a given HR will vary from day to day based on environmental and other factors such as sleep, diet etc so it’s important to run each day according to HR and not the pace suggested by a HR test.

What do I do on a hilly run? Do I walk up hills to keep HR on target or let the HR drift up?

There’s no hard and fast rule. Some people slow down on hills, others let their HR drift up. It’s fair to say that if it’s a very hilly run it’s probably best to forget about the HR.

Isn’t this just slow running, how will running slow make me fast?

Hadd base training can be very intense. It tends to involve a lot of time on your feet which can be tiring even if the runs are often at relatively low effort. Depending on fitness level the long sub LT runs can be both speedy and tough. In any event, as many people have found, and Hadd himself observes, too much fast training doesn’t necessarily lead to fast races. The aim is adapt the body by training at the right intensities, the racing speed follows from the adaptations to your muscles.

Do I need to be running 50 miles per week to do/benefit from Hadd training?

People have seen considerable benefit from running less that 50 miles per week at Hadd base training HRs. However the advantages do come from the ‘time on feet’ at the respective HRs. Ideally you should be looking to run for about an hour a day with a two hour run on Sunday, or look to build up to that if it would lead to a big jump in mileage from what you’re doing currently.

Can I mix an interval session each week with the Hadd training sessions?

It depends on why you want to do the interval sessions? If you’re trying to peak for a shorter race, say 5k or 10k, then you’re moving away from base training. You don’t need the intervals in the base training period when you’re better off focusing on the core 70-75% HRmax runs and the sub LT HR runs. If you’re moving away from base training to a peaking phase, intervals can come into play. Hadd advises his marathon runner to do a few 200/200 sessions as he gets closer to his target race. This 200/200 session involves running 25X200m at 5k pace, with 200m recoveries at a pace 15s (per 200m) slower. If for whatever reason you choose to include an interval session in your training it should replace one of the subLT runs, so as not to include too much hard running in a week.

Ok I’ve done a few months base training, where do I go from here?

This article just focuses on the base training element. Once you have developed a good aerobic base you will be in a strong position to switch to race specific training and Hadd indicates that when you have a good base such race specific training can be fairly short i.e. 6-8 weeks. However it can take several months to get to the stage where your aerobic base is well developed and once you’ve done your target race, or if you’ve been out with injury, it can be a good idea to go back to base training to rebuild your aerobic base.

Where can I find out more?

The original document "Hadd’s Approach to Distance Training" is found here Link (roll over me to see where I go) (alternative link Link (roll over me to see where I go) ) a Letsrun discussion between Hadd and another coach Antonio Cabral also contains useful insights Link (roll over me to see where I go) . If you have any questions its usually best to just post on the Hadd thread where there are lots of knowledgeable people who have followed this training.