Coaching Corner #2.2 - Understanding Speedwork

October 07, 2023

WARNING: If you have not read and understood THIS, then the following article is not for you. Once you have performed a period of aerobic ‘base building’ through easy effort running, which should be anywhere from 4-12 weeks depending on your level of conditioning, you should be able to incorporate different paces/intensities into your training. However, these are the sprinkles on top of the ‘easy cake,’ and need to be added gradually and sporadically. All the different types of runs below fall into the ‘Speedwork’ category, but they each have a different purpose. Whether your training is delivered by a coach or created by yourself, it is essential that each run has a purpose, not just on the day itself, but more importantly that the purpose fits into the overall training cycle.


1. Tempo

Tempo is a widely used and often misinterpreted term in running. Ask ten different coaches and you will get ten different answers as to what it means. For simplicity, I often use it interchangeably with a threshold run (see below). But there are some differences between the two. Tempo, like easy running, is an effort zone rather than a narrowly defined pace. It starts when we cross the aerobic threshold (outlined in article 2.1), working at 75-85% of max heart rate or 4-6 out of 10 RPE. The effort should feel comfortably hard. This is where your marathon pace SHOULD be, so this is an effort you should be able to sustain for 2+ hours. If your training schedule prescribes a tempo run, and you are gasping for breath after five minutes, chances are you are not in the tempo zone. This zone will vary depending on the conditions, elevation, your freshness etc, and therefore the pace could be marathon pace, half marathon pace, or somewhere in between.

Typically, tempo efforts are relatively long, and can be done in intervals (e.g., 3 x 10mins tempo with 2mins recovery) or single blocks (e.g., 30 minutes tempo). The purpose of the run is to improve your ability to clear lactate, to get comfortable with running at slightly faster paces for longer, and to improve your running form/economy at faster paces.

2. Threshold

The next level above tempo is threshold. The name comes from the fact that these runs are performed around our lactate threshold level. As it is a harder effort than tempo (85-92% max heart rate or 6-7/10), we are only able to sustain this pace for roughly one hour. Therefore, it should be quicker than your half marathon pace, but slower than 10k pace – for most well or moderately trained runners this ends up being around their 10-mile effort, so a 10-mile race is a good way of estimating this time. Given the change of intensity, threshold runs should make up less volume than tempo, and with longer rest periods. A typical threshold session might look like;

6 x 5mins @threshold with 2mins recovery

10 x 800m @threshold with 200m recovery

The primary goals of a threshold session are to improve your ability to deal with increasing volumes of lactate (therefore increasing your lactate threshold) and to familiarise yourself with the feeling of working hard.

3. Interval

Intervals, or fast reps, in my opinion, are performed far too often. This can be; 

Intentional – because there is a belief that you must run super-fast or give maximal effort when doing a harder training session.OR

Unintentional – if a tempo or threshold session is performed above the parameters of that particular zone.

Interval sessions are tough! They are designed to stress your cardiovascular system almost to the maximum. Hence, they should be very short duration (200-400m or 1-3mins) and very sporadic (elite marathon runners will perform less than 5% of their weekly volume at this effort, and sometimes not at all). The rest periods need to be long enough to allow full recovery.

The reason I am not a huge fan of these is twofold. Firstly, with increasing speed comes an increased injury risk. That alone should be enough to be cautious with them. Secondly, the classic training model for a novice athlete has always been based on starting with intervals, then progressing up to threshold and tempo efforts. The premise here seems to be start with the shorter efforts and build up to the longer duration ones. But I would argue that that needs to be flipped. Three sets of six minutes at true tempo effort is a much more gentle and safer introduction to speedwork than 10 x 400m intervals, especially when intervals tend to end up being sprinted by most people. Track sessions lend themselves to interval work, hence most clubs will do them with beginner/untrained athletes, but it is possible to run on a track for more than 400m, and not at sprinting intensity either!

However, they do serve a purpose. Running fast in training is still essential for running fast on race day. They are more relevant for those people who are specifically focused on a 5k or 10k training block, rather than half or full marathon distance. The typical club runner is almost certainly overdosing on interval work, but at the correct dosage they can be a useful part of your armour.

4. Race Pace

A race pace run should be what it says on the tin – a run performed at planned race pace! These may just be another name for an interval, tempo, or threshold session. For example:

5 x 400m @5k race pace – this could be an interval session

3 x 12mins @half marathon pace – this could be a tempo training session

Generally, I find these better for half and full marathons. Using the words ‘race pace’ rather than tempo or threshold can also focus the mind on the race event. The point of these runs is to expose you to the same pace as you will run on the day. It should be challenging but manageable. As marathon training requires a high volume of training and accumulated fatigue, it is normal to find the race pace difficult during the peak marathon phase. But the taper, extra training, race day environment and racing psychology should make it much easier on the day. If it constantly feels like race pace is too tough, then whether your time goal is realistic must be considered. In terms of preparing for the day, even more benefit can be gained from these sessions by simulating the race environment – same breakfast as race day eaten at the same time, the same clothes and footwear, the same number of gels etc. Make it as close to the race day experience as possible so that nothing is a shock on the day. For the marathon, and for the well-trained runner, long race pace blocks are a key component of the training plan. This could look like 4 x 5km or 3 x 8km at race pace – if these go well, they are a huge confidence boost for the day ahead.

5. Progression Run

The premise of a progression run is simple – a run which starts easy and gradually gets faster. But there can be a lot more complexity to it. Depending on the length, you may increase the pace every km/mile. Or for a longer run, the progressions may be more staggered (increase pace every 3km, for example). This can be a great option for an inexperienced runner who cannot tolerate a big marathon pace long run like the ones above – in this case they could do 75% of their long run at easy

pace, with the final 25% progressing to race pace. Another benefit of a progression run is that is allows you to be flexible on the day. Perhaps you are feeling more fatigued than expected before a workout. Instead of sticking rigidly to the planned workout and not having a good day, you could start easily, and if you feel ok after a couple of kilometres you can pick the pace up. Still feeling ok after the change of pace? Then pick it up again. You choose when the pace changes come. And if you cannot respond, just drop down the gears again. The most important thing for a progression run is to start easy enough that the multiple pace changes do not end up making you run faster than prescribed by the end.


Hopefully this article has helped you to decipher the often-confusing terminology in running training plans. Whether you are being coached or working independently, the key things to remember are;

  • Each run should have a purpose – if you are confused, something is wrong
  • Each run should fit into the overall picture – the weekly small picture, the monthly bigger picture, and the big race picture
  • Run at the pace or effort level prescribed – you don’t get any extra benefit from running faster. Instead, this may have a negative effect on the session and the wider training plan
  • For each of the above runs there should be a noticeable gear change – if your easy blends into tempo, or tempo blends into interval – your paces are not correct, and you should seek guidance on this in order to maximise your training workload

If you enjoyed this article and wish to work with Enda for 1:1 running coaching, you can find out more information by clicking HERE.

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