“Run slow to run fast” isn’t news to anyone, but overcooking easy runs is still one of the most repeated training mistakes by new and experienced runners looking to improve their times.
A common question runners ask when they start training for their first race – be that a 5k or a marathon – is: “What’s a good pace for me to run at?” The answer is different for every runner, and differs further depending on exactly what session they plan to do.
Polarising your training – or mixing up your running between easier, slower running and harder, faster running – is at the centre of any training plan focusing on improving times. That easier, slower running – sometimes referred to as zone two or base miles – will form the bulk of a runner’s overall mileage.
The classic pitfall a lot of new runners make is to run their easy runs too hard, and then struggle to hit their targets when they do their more demanding workouts because they’ve not recovered. This can leave a lot of runners training in the “grey zone” - not working hard enough to enjoy the adaptations of speed and tempo workouts, and working too hard to build up a solid aerobic base.
The aim of this article is to explore the different ways of measuring the intensity of a run. Gauging your effort in a consistent and reliable way ensures you can keep those “easy” runs easy, and keep your body fresh and ready for harder sessions.
Training to heart rate
This is the most precise method of gauging intensity available to runners. Either by using an electrical heart rate monitor on a chest strap which can pair with a watch or phone by Bluetooth or ANT+, or an optical sensor onboard a GPS watch, a runner can see their heart rate in real-time during a workout.
Everyone will have their own individual heart rate zones, but without access to a lab for a full work up, a good starting point is the Dr Phil Maffetone system (MAF) of deducting your age from 180, and trying to do your easy runs at or below this heart rate value. For example, a 40-year old runner would try and do their easy runs with their heart rate below 140 beats-per-minute (BPM).
For beginners, and even people with a high level of fitness who haven’t tried polarising their training before, this may be quite challenging. To adhere dogmatically to the Maffetone 180 formula could be reductive and off-putting in the early stages, and potentially result in some walking to keep the runner’s heart rate down. However, having the HR data from your running will allow you to gauge effort relatively, and track improvements in your fitness over time.
- If you don’t have a heart rate monitor, you will need to purchase one.
- You can become too reliant on the data - if your battery dies, or a sensor is compromised, it can be frustrating.
Despite some minor drawbacks, a heart-rate monitor presents the most reliable option for keeping the “easy” runs easy, as it removes a lot of guesswork from the training process.
Training to pace
Training to pace is a concrete measure of how your easy runs compare to your goals for a specific race. After all, your Boston qualifier is based on the pace you can sustain for 26.2 miles - “it” doesn’t care about your heart rate. Of course, exactly what pace range should constitute “easy” for an individual can be difficult to work out. For this type of training, if you don’t have a recent result to work from, it would be productive to do a 5K race or time trial as a benchmarking exercise.
There are numerous online pace calculators that will ask for a recent race result, and then be able to calculate training paces off the back of that - suggesting what your easy pace should look like, as well as paces for your more intense sessions. A couple of good ones include the Jack Daniel’s VDOT calculator (taken from the comprehensive distance coaching book, Jack Daniel’s Running Formula), and the Runner’s World calculator.
Without access to a track and the will to do all your running on said track, or unless you live somewhere that has mile or kilometre markers along the roads (these places do exist, apparently), to train by pace will require you to either carry a smart phone with a good running app downloaded, or wear a GPS watch. To ensure the most consistent feedback on your intensity by this method, you’ll want to set your watch to show lap pace, and your units should be in kilometres. The shorter the interval, the less likely you are to go off too hard and have to slow down, and vice versa.
- Your easy pace on the flat could become quite challenging to sustain on hills.
- Training to pace doesn’t take into account the weather - be it wind, humidity or higher temperatures which will force your cardio-vascular system to work harder for the same result.
Training by feel
The most simple, cost-effective way of gauging the intensity of your runs is by feel. This is exactly what it sounds like. It doesn’t require any equipment, and it doesn’t commit you to a specific minutes-per-kilometre pace range to beat yourself up over if you fall short. You simply run based on how you feel.
The obvious pitfall here is how reliable an individual’s perception of “easy” actually is. This is especially difficult for people who have a high level of fitness taking up running or picking it back up after a hiatus. Any pace short of sprinting will probably feel easy until it doesn’t. Your half-marathon goal pace might feel easy for 45 minutes, but having to double or triple that effort can really expose the difference between what’s an easy pace and what’s actually a manageable pace. Just because you can manage a 40-minute 10K every run doesn’t mean it’s going to help you smash that sub-three marathon.
There are a few good techniques for quantifying how your training feels, but the most famous and widely utilised is probably the rate of perceived exertion (RPE). RPE typically assigns a grade from 1-10 to each activity, with 1 being a light walk, and 10 being an all out sprint. Over time, you tune into how your body feels on this scale, and plan your easy runs accordingly - typically scoring a 4-6 for your easy runs. (Opinions will vary on what the exact score for an easy run should be).
- Subjective to the runner, potential to over and underestimate perceived exertion.
- Can take a long time to truly tune into and use RPE effectively, a lot of guesswork early in the process.