The 5k is a great distance as it’s so inclusive. It caters for the sub-16, sometimes even sub-15 veterans whilst also being great for couch-to-5k beginners looking to begin their running journey. Whilst the half marathon is my favourite race distance, 5k is one I often come back to in between training blocks, and it feels like I’m forever trying to improve my PB. During this time, I’ve read and listened to various sources with regards to the best way to get faster and, in all honesty, there’s a lot of information out there, some of it contradicting. In an attempt to sift through this, what I’ve discussed below is either what I know works, or what seems to make sense to me.
The most important thing to remember for a 5k is that, whilst it is the shortest of distances in terms of road running, it is actually one of the longest in terms of track running. 5k is not a short distance and requires a reasonable level of stamina. Achieving, and maintaining, a good endurance base is key to success in the 5k. Unlike the half marathon, where it is not seen as essential to have run the race distance in training, training for the 5k would ideally see you running further than the race distance. The key to building this endurance base though, is running slow, or easy.
There’s so many benefits to doing this, all of which have been scientifically proven, although I won’t go into that here. In short, it builds endurance and is easier on the body, which both allows you to push harder on speed sessions and also offers active recovery in the days after a hard session. It is these runs that will allow you to go further, and for longer.
So, how easy should easy be? How slow should you be running these sessions? Of course, this depends entirely on the individual. If you run with a heart rate strap (specifically a strap, not an optical wrist-based monitor) then you want to be in HR zone 2 for the majority of these runs. You may creep into Z3 on tough, hilly sections, but for the most part you should be aiming for Z2. In terms of pace, a general rule is to be running no quicker than 2 minutes per mile faster than your goal 5k pace. My current goal pace is 6:45/mile, with my recent tested race pace being 6:55/mile. I run my easy runs no quicker than 9:20/mile, just as an indication. I posted about easy runs almost exactly a year ago, so please take a look if you would like any further information (here). Concern yourself more with time than distance on these runs. Depending on how long it currently takes you to complete a 5k, you don’t really need to be going out for longer than 60-75 minutes.
Once you’ve built up a good running base, and only once you have done so, it’s a good idea to start introducing some speed work. Speed work, or intervals, is a collective term for short bouts of faster running in the middle of normal runs. These are generally split up into threshold and intervals/reps.
Reps often get grouped with intervals in many of the online training plans, but I like to distinguish between the two. I take repetitions as being really short intervals, up to around two minutes or 400m, with a similar recovery time before the next hard effort. As they do not last very long, the idea is to go almost all out. You want to be aiming to hit at least race pace during these short sessions, ideally slightly faster, and again take rest periods a maximum of the same duration as the rep. I consider intervals to be slightly longer in duration, up to around five minutes. Being slightly longer in duration, these are not to be run quite so hard as reps, although you should still be pushing. The rest periods will vary depending on what you’re aiming for. If you’re trying to hit a particular speed, then you can take longer rest periods, but if you’re trying to train for race simulation then shorter periods will help, as you will be hitting the next interval before your legs have had enough time to fully recover.
Threshold running is arguably as important as easy running, provided that it is carried out correctly. A threshold interval will be anything between 6 minutes and 40 minutes in duration (more likely at the lower end if you are training for a 5k) and should be run at a ‘comfortably hard’ pace. Running at, or around, your lactate threshold pace trains your body at running harder/faster for longer intervals. This ultimately changes your lactate threshold, meaning you can run faster before the point where your body produces more lactate than you can flush away. Getting this pacing correct can be difficult, so there a few ways in which you can try to determine an accurate pace for you. First of all is heart rate again, where threshold running is completed in HR zone 4. Another way is the speech test. If moving along at the correct effort, you will only be able to speak three or four words at a time. Completely out of breath, you’re going too hard. Able to string sentences together, you’re not going hard enough. Another way to determine pace is using an online calculator. There are various about, the VDOT02 and the McMillan running calculators to name just two. Enter a recent race time (recent best effort parkrun would work) and the calculator will provide you with an estimation of your threshold pace. Use this for your threshold workouts, although be sure to account for hills whilst you are out and try to maintain effort as opposed to pace.
In terms of planning your runs, assuming you’re not working to a specific training plan, aim to slowly and progressively bring in some speed training. Ideally you would want to be running a minimum of 3 days per week and, if you’re not yet familiar with speed workouts, then introduce one per week to begin with. If three runs per week is your norm, then two easy runs (one ‘long’ and one short) and one speed workout would be sensible. If you can already hit your target race pace, then you would benefit more from threshold and interval workouts as opposed to reps. You can alternate each week.
If you run four times per week, then I would suggest three easy runs and one speed session, until you are comfortable with speed work, at which point you can progress onto two easy days and two speed days. I would suggest the speed days involve one threshold session and one interval or repetition workout. If you run more than four times per week, then I would still suggest just the two speed days, as you don’t want to put too much load on your body. Running easy will still improve your running economy and give you ‘time on your feet’ so three, four or even five easy days would nicely accompany two harder workouts, just make sure those easy days are really as effortless as possible. There’s a lot of support out there from experts on the benefits of an 80-20 split in terms of easy and hard running. 80% of weekly mileage easy, 20% hard. Matt Fitzgerald is a big advocate of this and I’m told his book is very good (80/20 Running: Run Stronger and Race Faster by Training Slower).
A good way to progress through your your self-built plan is to first of all build a good base of easy, endurance running. Once you’ve done this, whilst keeping within the above training splits, move on to some threshold sessions to build your lactate capacity with some short rep sessions to improve your speed. Then, as race day approaches, include some race specific intervals with short rests. For example, you may start introducing reps with some 400m repeats, with 2 mins rest, but further along in your plan you may wish to do some 1km intervals with just 60-90 seconds rest. Manage to perform these at race pace and should go into race day with confidence of hitting your targets.
A final few points regarding training for a 5k, or training for any race really. First of all, don’t give 100% in training, save this for the goal race. Pushing to your maximum takes it out of your body. Don’t risk this during training. Another key point is to only try for a PB once every so often. With parkruns taking place every week, there’s a temptation to go for a PB each time. Don’t, go for a PB once per month maximum. Put your faith in training blocks and allow them time to work, rather than going 100% every Saturday. Finally, different approaches work better for some than others. Find out what works for you and what offers the biggest benefit to your training. The advice given here is what has worked for me, and is a culmination of research carried out myself into how I can make myself a faster 5k runner. As ever, feedback welcomed.
For any questions in terms of speed sessions, I’ve included some examples below of the different run types discussed above.
8-12 x 400m with 60-120 seconds rest
8-12 x 90 seconds with 90 seconds rest
15-20 x 1 minute with 1 minute rest
10 x 60 second hill sprints with recovery jog back down
5 x 1km with 1-3 minutes rest/jog recovery
3-6 x 5 minutes with 1-3 minutes rest/jog recovery
6 x 2-4 minute hills with recovery jog back down
8 x 3 minutes with 90 seconds – 2 minutes rest/jog recovery
2-3 x 7-10 minutes with 2 minutes recovery jog
3-6 x 6 minutes with 90 seconds – 2 minutes recovery jog
2 x 20 minutes with 5 minutes recovery jog
40 minutes, following a substantial warm up and including a long cool down afterwards