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John Armstrong

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John is the webmaster of Mornington Chasers and is qualified as a Coach in Running Fitness. By day he is a mathematician. He has been coaching for the club for two years and helped set up our beginners programme. His marathon PB is 2:43:53.

Running and Social Distancing

Posted on March 26th, 2020 by

We’re all just learning how we should be running while social distancing. At Mornington Chasers we’ve been discussing this a lot with each other on Facebook to figure out how to handle it. This is what we’ve learned.


Laurie, our club welfare officer, tried the experiment of taking a 6 mile walk (always at 2m distance obviously) to observe runner and pedestrian interaction. She forgot her love of running and get into the mindset of someone who walks but doesn’t run. Here are her tips:

1. If you do run, just focus on the pure unadulterated joy of still being allowed outside to do this. Don’t focus on your Garmin or your speed. Approach running like a precious freedom that you might lose if not used correctly
2. Slow down and, also, slowdown. You can also take this tip with an extra pinch of ‘slow down’
3. Even if you know that you’re extremely skilled and nimble at dodging people and crowds, just pretend that you’re not – just seriously slow down or walk as you pass others. Especially people walking in household groups and families.
4. Know that if you are running behind someone who is walking and you’re breathing heavily and the sound of your feet are pounding the pavements, that this will be disconcerting to walkers around you. It doesn’t matter that you are a kind and considerate, they don’t necessarily know this. So, slow down.
5. If you find yourself in an area where you are completely alone and can see far into the distance, then use this to pelt out some speed and sweat. But – don’t do this when you are heading towards corners or where other people are nearby
6. Whenever anyone (seriously, anyone) makes way for you to run, then go out of your way to shout ‘thanks’, wave or just beam your biggest smile at them. You’d be amazed by how reassuring that is to someone who doesn’t run. It will let them know that as runners, we don’t always expect right of way and we are nice people.
Some other tips I’ve heard:
  • Don’t combine running with shopping. Nobody wants to be near you if you are breathing heavily and sweating right now.
  • Don’t running in groups even with people you are isolating with (except for children). You are making it harder for others to pass and no-one but you knows that what you are doing is legitimate.
  • Run at the edge of the pavement to make it clear you’re the one who will give way.
  • Some advice from an epidemiologist in the New York Daily News: “Try not to spit. If you have to, move to a less-traveled part of your route such as off the road in the grass”


I went for a 16 mile run on Sunday into central London just before the rules were tightened up to see if I could run that far without ever going within 2m of anyone. Even though people were being a bit silly last Sunday, it was perfectly possible to do this, and it should be even easier to avoid going near others now. Here’s my advice on how to plan your run to maxmize social distancing.

Covent Garden on my social distancing run

Covent Garden on my social distancing run

1. Make it a game. Many people will not want you to go within 2m of them, so make sure you never go within 2m of anyone at all. They are the rules of the game. If you have to double back or dart down a side street, do it. If you have to stop or walk, do it.
2. Vary your usual routes. Try running somewhere new that will be unusually quiet. I ran to Covent Garden and it was deserted. The football fields in parks are usually out of bounds because of the footballers, but they are now the perfect place to go for a bit of faster running. On the other hand you can’t run along canals and keep 2m away from people, so they are forbidden. You can’t cross long bridges or run through long tunnels. Avoid high streets, but side streets are empty.
3. Keep on the grass. Paths are for wimps. Be willing to get a bit muddy. If you see a keep off the grass sign, feel free to ignore it. If a parkie chases you, practice one of your sprints.
4. Avoid unnecessary travel to and from your run. As far as possible, it should start and end at your front door.
5. Loos are closed. Know your limits.

Training Racing and Goals

I spoke to our former club coach Tom Craggs who now coaches one of England’s veteran running teams and his advice to his athletes is to see this period of social distancing as the off-season. Training for performance is a cyclic affair where you try to peak for an important race (maybe that’s the Olympics, a marathon, or your club championship). Once that’s over, you give yourself some time to recover and consolidate your gains. It’s a pity that most of us missed out on our big spring races, but it is time to let that go, we did most of the training and got the fitness benefit we wanted anyway, so it’s not such a big loss.

Since it’s now officially the off-season, you can wind down your distance and ease off a bit on the speedwork.  Focus instead on improving in the areas you might let slide a bit during your peak training. Now is a great time to establish a strength and conditioning programme that you can stick to once you start running again. Similarly, this is a superb time to be working on building basic agility, balance and coordination or to work on your flexibility. These are all things you can do at home, maybe with the kids you are having to home school. At Mornington Chasers, we’re planning to have online strength and conditioning sessions together with some dance sessions and pilates to cover all these bases.

As it’s the off-season you wouldn’t normally be racing. We’ve all grown addicted to regular races, especially because of parkrun and quite a few people are coming up with ideas for online races. At the moment, I’d discourage online racing because I haven’t seen anyone figure out a format for an online race which encourages people to stick to the etiquette for running during social distancing. If anyone cracks this problem, I’d love to get involved.

If it’s the off season and you’re not going to be racing, that means you should be avoiding setting yourself inappropriate training goals. Now is not the time to be trying to increase the distance you run. Running for speed is OK to an extent, but you should never compromise on the etiquette. If you are going to be running on the grass carefully dodging other people you won’t be able to be as obsessive about your times. I think the best kind of running goals at the moment are technical ones – for example can you improve your technique with some running drills and by doing regular core workouts?  You can set yourself a fitness goal too, but that could be related to your flexibility, your strength or your coordination. Some good goals you could set yourself would might be to do 50 press ups in a row (or 5, or 500), to touch your toes or to dance the Charleston.

This doesn’t mean you have to forget about running entirely. While we are allowed out, it’s a good idea to keep doing some strides and drills during this period somewhere you won’t get in other people’s way, perhaps on playing fields or down a dead-end. And if you stick to the grass you can still give yourself a decent work out while avoiding others and being easy for others to avoid.


We’ve only been social distancing for a week and half so there’s a lot to learn. In Spain running is currently banned and in France you can’t run more than 1km from your home. We’re incredibly lucky to still be allowed to run, so let’s make sure we keep it that way.




My Post Coronavirus Plan

Posted on March 13th, 2020 by

We all knew London would be postponed, and good on the organisers for putting the health of the elderly and those with lung conditions as their top priority.

I’m no epidemiologist, but I thought it might be helpful to say how I plan to respond.

Firstly, I’m shifting my training focus to Paddock Wood. I’ll immediately switch to that schedule. I have a place in a backup marathon but if I run it at all I’m not going to compromise my immune system by going at it full tilt. I know from experience that I get run down post marathon and so I’m not going to take any risks. I have no idea if there is any evidence that running a marathon hard will really be a problem, but I don’t care. My priority is my long term health, so I’m not going to chase a marathon time this spring.

Second, I’m only going to do races if this fits with the advice we are given on travel and gathering sizes. If Paddock Wood is cancelled or travelling there is considered a bad idea, well, so it goes.

The fitness I’ve built up can be used to good effect to knock out some fast short races. There are some small local races that seem perfect. After Paddock Wood, the athletics season starts with a meeting at Parliament Hill and Donal will be putting together a training plan for the Golden Stag mile. Last year I was knackered from London at the Golden Stag. This year, I plan to ace it.

We’ll need to come up with a schedule for early autumn marathons that makes the most of the summer league and the athletics meets to get us in top shape. Should be fun figuring out how to do this, and should mean some cracking long runs in beautiful weather. We’ll keep you posted…



Spring Training 2020

Posted on January 2nd, 2020 by

The Thursday track sessions this spring have been designed to fit in with our training schedules for London and Brighton marathons and for Paddock Wood half marathon. You can see the full schedules here.

To use the schedules, you should customize with a realistic target time. If you are running a first marathon, then you should normally base your target on a recent half marathon, assuming you are planning to commit to a similar number of training days each week. If you are targeting a PB then be ambitious, but realistic. If you decide you want to increase your training from 3 to 5 days a week (say), then do this gradually over the first few weeks of the schedule.

Our schedules contain a lot of practice races, designed around the events we like to run as a club. Most of these races are free to enter, but you might want to sign up now for the Fred Hughes 10 in St Albans and the Wokingham Half Marathon. They will both sell out pretty quickly, so get your skates on if you fancy doing either of these.

The other practice races will appear on your schedule if you choose to train on Saturdays. These include some cross country and lots of parkruns. Don’t run the parkruns hard every week, use them as a way to customize the schedule to how you are feeling. If you’re tired, give yourself a break. If you are full of beans, then go for it.

If you have a different target race in mind, or have different preferences for how to train, then use our schedules to tell you what will be happening on a Thursday and what races are coming up so that you can build your own schedule that fits in with the club. Our Thursday sessions would easily fit into a training plan for any distance from 5K up, but you might, for example, replace a Highgate run with some some hill sprints if your focus is on shorter distances.

Paddock Wood Half Marathon

Paddock Wood is an excellent half marathon for anyone new to half marathons or who is looking for a PB. It is a flat, fast course on roads. It is a one lap course with a relatively small field, so you there won’t be crowds of people getting in your way.  We’ve also selected Paddock Wood as the perfect tune-up run for London marathon.

If you are worried about transport, then there is a direct train to Paddock Wood from Charing Cross arriving 28 minutes before the start, which is right by the train station. If there is demand, I’ll look into arranging alternative transport for those who want to get their earlier.


Calculating your handicap

Posted on April 30th, 2019 by

I’ve calculated the handicaps for our handicap race in Highgate Woods as follows.

  • For every race over the last two years, look at your age graded percentage. We can only calculate this for certain event distances.
  • Take off a further percentage according to how long it is since you achieved this result. If it was a year ago, we would take off one percent. The idea is that if you have been ill or injured you still have a decent chance.

This gives your handicap as an age graded percentage.

Next, we work out what 5K time this age graded percentage corresponds to. Then we use the calculator on the website to work out your predicted time over the race distance (which is a little over 5K).

This number is your handicap. Everyone will start at such a time that if there handicap predicted their race time perfectly, we would all finish simultaneously.

To see your handicap visit the results page of our website and search for your results.

If you think your handicap is not appropriate you can tell me why it is not appropriate and tell me your own predicted time. I’ll decide whether I agree with you or not. My decision is final.


Book Your Spring Training Races

Posted on December 2nd, 2018 by

I’ve put together a training plan for London Marathon 2019. We’ll also have a half marathon specific schedule building up to Croydon half marathon which should be up by the New Year.

We’ll use the same key training races for both schedules, so book your place and get them in your diary now.

  1. Fred Hughes 10 OR Benfleet 15. Fred Hughes is a fast flat road race. Benfleet 15 is a slow hilly trail race. Don’t even think about Benfleet unless you are confident to run that distance in January. Think of it as roughly equivalent effort to 20 miles on the road.
  2. Southern Cross Country Championships at Parliament Hill. This is a brilliant race and a must for any Chaser who owns a pair of spikes. Click on the link to enter (you will require England Athletics membership too, so request that via your Chasers account if you don’t have it already).
  3. Wokingham Half Marathon. This isn’t even mentioned in the schedule yet. It will just be an alternative to the current published schedule for those who want a half marathon test at the end of Feb. The scheduled alternative is to do a long run the next week building in a fast section at the Regent’s Park 10k.
  4. Croydon Half Marathon. Get your discounted tickets from our online store.


Marathon day essentials

Posted on April 17th, 2018 by

  • Race number, pinned to vest
  • Shorts
  • Shoes, chip attached.
  • Socks
  • Bag with number on it.
  • Watch
  • Pacing wristband *
  • Mobile *
  • Fancy dress costume *
  • Vaseline, for anywhere potentially chafy
  • Sunscreen
  • Sunglasses *
  • Hat *
  • Plasters for nipples (or more vaseline or a bra)
  • Gels, jelly babies, carrying device
  • Imodium *
  • Loo roll *
  • Beetroot Shots *
  • Drink for while you are waiting, maybe a bite to eat.
  • Bin bag or disposable clothes.
  • Oyster card. They say its free travel on race day but not everyone in TFL seems to get the memo.
  • Something to wear afterwards *
  • Lucky heather *

* = optional

I think that’s everything. See you at the start or at the Pineapple.


Mental Preparation

Posted on April 10th, 2018 by

Just two weeks to go to the London Marathon. If you’re racing it you’re probably beginning to feel the nerves.  If so, that’s good. We want that excitement and nervous energy on race day. Here are some thoughts to get you mentally prepared.

Have a Plan: If you haven’t done so already use our pace calculator to check whether your goals are realistic and formulate your race day plan.

Part of your plan will be your pacing plan. Some possible suggestions are: stick with the pacers for a particular goal time; aim to arrive at half way 1-2 minutes ahead of goal pace to allow for a slight fade at the end of the race; pace it absolutely evenly throughout; go for a slight negative split (that is aim to do the last half slightly faster). Each of these options has their merits, so I’m not going to pick one for you. But what I will say is that you shouldn’t aim for more than 2 minutes ahead of goal pace at half way and you should go in with a plan. “Go out hard and see what happens” does not count as a pacing plan.

On race day you will be sorely tempted at two points to break the plan by going too fast. That’s at the start and half way. As in practically all races most people set off too fast. Let them shoot off, while you pace it right. If you’re starting further back at London, accept the reality that it’s going to be very crowded at the start. Don’t waste energy weaving and getting angry with other runners for being in your way. Take it easy and think of the big guy in front of you as a useful windbreak. The second moment when people decide to waste energy in London is half way. I find that everyone starts waving at the crowd and speeding up for no clear reason. Again, let everyone else zoom off. You will have caught them all up again by mile 15.

Another part of your plan will be your hydration and nutrition plan. A hydration plan perhaps isn’t such a big deal for London as there are very frequent water stops, but if you are relying on the Lucozade sport they hand out, you’ll need to know exactly when to expect it. In smaller marathons you may only get water once every 5K in which case you definitely want to be prepared. Your nutrition plan should start several days out from race day and will certainly include your race day breakfast and everything you plan to eat during the run. Do listen to your body, however: if your stomach starts complaining about the gels, stop eating them; drink if you’re thirsty; don’t take on excessive amounts of water.

Stay in the Moment: On race day, try to focus on where you are in the race right now. Are you running with good form? Are you following the blue racing line? Are you keeping to an even pace? It can help to run an occasional check on yourself asking how everything feels to make sure you are staying relaxed and comfortable. If you’ve been working on an area of your form, think about that but don’t try to force it. For example, I’ll be monitoring myself to try and keep my head up and avoid crossing my arms. Try not to think about that beer you’re going to have at the finish as you’ll find that distractions like that do actually slow you down a little as you lose focus.

A Mantra: A mantra is any phrase you can say to yourself to focus your mind. Go for something positive. Nike recommends “Just do it”, I like “I have found the line and its direction is known to me. Absolute trust keeps me going in the right direction” (Talking Heads – The Good Thing). You might also try counting. Paula Radcliffe would count to one hundred over and over again to help keep focus. I like to just count and see how high I get. My PB is over 8000.

Enjoy the Cheers: For me the two highlights of the London Marathon are the cheers from the Chasers cheering squad. You’ll get the cheers at about mile 13.5 and mile 22. I think they’re a huge psychological boost. The crowd will be cheering you the whole way too. Smile and look around you to take it all in. Enjoy the fact that all these people are out there supporting you and want you to succeed.

Positive Visualisation: As race day comes, you will find you dwell more and more upon the race ahead. Use this as an opportunity to mentally rehearse your race day plan. Visualize yourself running in controlled and comfortable manner from the start. Rehearse your mantras. Picture the crowd cheering you on. Picture yourself smiling as you take it in. Picture yourself staying focussed throughout and holding your form to the end.

This week’s training

To help you prepare your mind for race day, this week includes a marathon pace fartlek on Thursday and a hard Parkrun on Saturday.

The hard Parkrun is a practice for staying focussed andlooking at your form. If your training has been going well and you get a PB that’s a bonus, but you’ve been marathon training not 5K training so don’t worry too much about your time.

The marathon pace fartlek is a comfortable run where you run some of it at marathon pace as you feel. This run is about getting outside and just enjoying running without tiring yourself out. It’s about running comfortably, sticking to a sensible pace, looking around and having a nice time. There aren’t any more rules to the run than that, its all about doing the kind of running you enjoy as a reward for all that hard training.


The Taper

Posted on April 1st, 2018 by

If you are following our schedule for the London Marathon, you have just started your taper. For those of you doing Brighton or who are racing a marathon next weekend, your taper should be in full swing.

A taper is a period of gradually reduced training just before a big race. The idea behind it is simple. It takes about a month for any training you do to have a positive impact on your race performance. However, training does make you tired and that will have a negative impact on your race performance. So you should reduce your training before a big race in order to get the best possible time. This is true to some extent whatever the distance, but it is particularly important for marathons.

If you’ve been following our London schedule, you should have been doing a lot of very hard training over the last few weeks. The chances are you’ve been feeling a little tired as a result. Our schedule should have pushed you about as far as it is sensible to go without risking too big a chance of illness or injury. It’s time to ease off. You’ve probably heard about elite athletes who aim to peak at the Olympics. Our schedule is designed to get you to peak on race day.

The first week of the taper feels a lot like business as usual, but if you look closely at our schedule you’ll see that there is a small reduction in effort from the last few weeks. In particular the long runs are not so long any more.

In the second week of the taper, you’ll begin to notice the reduction in training. In particular, there’s no track session in the second week. You will be doing a marathon pace fartlek instead (I’ll explain some other time).

In the third week of the taper, you should scarcely run at all.

You might start to panic that you haven’t done enough training and be tempted to put in a little more work than the schedule says. Don’t worry, you have done enough training. Yes, I know you had to miss some training at one point due to injury, and there was that session you missed because you were working late, but this happens to everyone. You’ve done the work, if you try to do more now you’ll be doing more harm than good.

The final week of your taper is critical. You have to do a lot of resting. You may actually hate this. You may start to feel nervous tension building. You mustn’t go on a run just to calm your nerves. We want that nervous energy still in place for race day.

Don’t be tempted by other activities in place of running. So no gym work during the taper. No decorating the house. No gardening. No overtime. No long walks. No sight seeing. No swimming. No acrobatics. No heavy petting*.

So download a Dan Brown/E.L. James/Melville onto your kindle, find yourself a good box set on Netflix, and start relaxing.



* The heavy petting comment is a joke. It is perfectly OK to have moderate to vigorous sexual intercourse during the final week of the taper. However, it should not be attempted during the race except in the portaloos provided.



20 miles

Posted on March 22nd, 2018 by

If you’re following our marathon schedules this weekend’s long run should be a bit of a celebration.

If you’re doing the Brighton schedule, it should be the easiest long run you’ve done in a while and should feel pretty comfortable. Given that it’s still a long way by any normal standards, this should make you realise how far you’ve come.

For those following the London schedule, this weekend is a 20 miler. For many of you that means its your longest training run, so make sure you enjoy it. Go somewhere nice and take it easy. Bask in the glory of knowing that you can now run 20 miles continuously.

Some of the faster runners who have already achieved the distance will want to do a bit of marathon pace, but absolutely no more than 10 miles at that pace. 5 miles easy, 5 miles steady, 5 miles easy, 5 miles marathon pace might be a good option. But I’ll say it again, if this is going to be your longest run, do it all easy.

Are you worrying how you will ever run 26 miles at race pace? If so stop worrying and have faith. Right now you are knackered. You are not in the ready to run 26 miles at race pace. It takes about a month before the benefits of a training session can be felt. That’s because you need time to grow new muscle etc. So in a month you’ll be even stronger than you are now. Even better, we’ll be lowering your training workload. The next month will be about recovery. On race day you will be totally fresh. Prepare to be amazed what you can achieve.

But, and this is important, you will only feel like that if you have the recovery you need. If you foolishly decide to run a 20 miler at race pace you won’t have time to recover. You will have thrown away your marathon on a training run. So follow my advice and don’t do more than the schedule says.

Where should you do this 20 miler. I strongly recommend going to Gade valley and doing the run there. Not only will it be an enjoyable change of scene, but they’ll hand out water on the way round. That means this is the perfect opportunity for a marathon dress rehearsal. So wear the clothes you have in mind for race day. Take the gels or sweets you’ll be eating. Try out your race day nutrition plan – so that might mean an early dinner the night before and maybe try out your beetroot shots or Imodium if you want to try them on race day.

Gade Valley is just a couple of train stops from Euston. Entry is on the day only for £10. There’s tea and cake when you finish. Hope to see you there, but if you can’t make it, take it easy and make sure you enjoy your biggest training run.




The Chasers Pace Calculator

Posted on March 11th, 2018 by

We have a pace calculator on our website which you can use to figure out what you might be able to achieve in a race and also what sort of pace to run in training.

It’s pretty straightforward to use except when it comes to figuring out your marathon pace, but it gives you a range of three possible marathon times.

The reason for this is that the marathon is a pretty extreme event, so it is hard to predict a marathon time based on shorter distances. So rather than give you a single figure I think it is better to show you a range.

The “Optimistic” time is based on a formula devised by Peter Riegel in 1977. This is the formula used for all other distances and it is pretty accurate for short distances. It predicts a marathon time only a few runners actually achieve (though some do achieve it, for example it predicts my times very well).

Ian Williams of Fetcheveryone had a look at the data for his runners and wrote an article about it that you can read here. I’ve used this article to come up with our “Conservative” time, though I actually used a different formula which should improve on it (see Geek’s corner below).

I call this time “Conservative” because it attempts to work out how the average runner will perform. But this average includes all the idiots who haven’t trained properly, who have set off too fast, or are running dressed as a chicken. I think you should be able to achieve the Conservative estimate if you train and race sensibly.

Finally with have the “Pessimistic” time. This is also based on the Fetcheveryone data but assumes that you will be roughly in one of the bottom 95% given your half marathon time. I think it is helpful to show the full range of marathon times, but I’d recommend you try to achieve a better time than this. I mean, you’re planning to train well and race sensibly aren’t you?

I’d recommend that when racing a marathon you should target something between the optimistic and conservative times. If you have raced a marathon before, you will have some idea of which of the predictions works better for you. If you haven’t raced a marathon you might want to err on the side of caution to make sure you enjoy the race.

When you use our calculators or schedules you can choose whether to go for the optimistic, conservative or pessimistic estimates by saying whether you or biased towards longer or shorter distances.

Geek’s Corner

The Riegel formula is:


What Ian Williams of Fetch everyone asked is whether the power 1.06 in this formula is the best choice. He studied how half marathon times predicted marathon times and found that the best power varies quite considerably from runner to runner, but a value of 1.15 would work for the median runner.

In his article he also drew the following graph showing how the best choice of power varies according to the half marathon time.


The correct power for the Riegel formula (the Riegel number) by half marathon pace. The graph comes from the article by Ian Williams linked to above.

The red line in the graph shows what value you should use instead of 1.06 to predict how the median runner will perform given their half marathon time. What this shows is that the basic shape of the Riegel formula doesn’t work so well since no single power works for all times. Since the red line in the graph looks roughly straight, I decided to let the power used in the formula vary linearly from 1.10 for an 80 minute half marathon runner to 1.20 for a 2 hour marathon runner. I also decided that for runners faster than 80 minutes I’d cap the power from below at 1.08. This is how I calculate the “Conservative estimate”.

For my pessimistic estimate I just made sure that the conservative estimate was half way between the optimistic and pessimistic estimates. The graph suggests this is a fairly reasonable thing to do.

Of course, one could try to produce a more accurate calculator by examining the data closely and taking more factors into account. If you are a computer scientist looking for a project, why not train a neural net or similar to predict people’s times? In practice, I think these formulae are accurate enough. They give a decent impression of the range of possible times you might achieve and are a useful reminder that we are all different.