Warning, here’s a slightly more technical piece about something that doesn’t really have a good word in English, so I’ll use English, like everyone else. The thing is DROP, which indicates the slope (fall) of the sole of a running shoe. The difference between the highest point of the heel and the lowest point of the sole at the toe. If the sole is 35mm thick at the heel and 27mm thick at the toe, then the drop is the difference between the two, i.e. 8mm.
There are 4 levels to distinguish when talking about drop:
- zero drop
The drop is 0mm - Low drop
Low drop A drop between 1 and 4mm - Mid drop
5-8mm drop - High drop
Above 8mm drop
Why is drop important, why should we even bother with it?
Beginning runners, and often even more advanced runners, simply suffer from drop. In other words, they look, buy a running shoe and simply live with the drop of that shoe. But the drop affects a lot of things, which are:
- Stride count
The lower the drop, the easier it is to increase the number of steps and thus reduce the length of the steps. It makes sense that a higher drop makes it harder to achieve a high step rate. I wrote about the importance of the step count in this post, it’s worth a read. - Touching the ground
The lower the drop, the more it encourages the runner to land on the midfoot or the front of the foot. A high drop encourages the runner to land more on the heel. In addition, the benefits of a low drop are difficult to exploit for runners who arrive on the heel. On the other hand, a higher drop can help more with shock absorption and rollover for heel finishers. - Injury, load
A low drop tends to put more stress on the ankles and feet, a higher drop tends to put more stress on the knees and hips. It’s also worth noting that one study (https://pubmed.ncbi.nlm.nih.gov/27501833/) found that lower drop is less likely to cause injury in novice or occasional runners, while regular runners are at higher risk of injury in shoes with lower drop
What should you decide when choosing a drop?
Obviously we are not choosing a drop, we are choosing a shoe, but all shoes have some drop. To decide, the following things need to be thought through carefully:
- Distance
If you want to run longer distances, you need to consider that the running motion changes as the distance is covered. We are less able to run nice and regular at the end of a longer distance, so we are more likely to beat our heels to the ground, so a higher drop may be preferable at this point. - Touching the ground
For runners who are mostly midfoot, or coming to the front of the foot, a lower drop will be more appropriate. This is also true for those who want to learn the midfoot or toe touchdown. The higher drop will definitely suit those coming in on their heels better for their run. - Injury
Those who have been injured or know they are prone to injury should note that the low drop causes ankle and foot injuries, the higher drop causes knee and hip injuries more. - Comfort
Habituation is a big one, and this is true for the drop as well. For big changes, a new shoe can provide a serious sense of discomfort. This is most common when changing from a normal or higher drop shoe to a low or 0 drop shoe - Terrain conditions
For those who have heard of proprioceptive training, this explanation may be familiar. Our body is imperceptibly trying to correct our balance according to the ground conditions. The fact that we don’t fall over on a bumpy surface is due to our body correcting, almost unconsciously, by subtle muscle contractions. The more natural a shoe is, i.e. the closer it is to drop 0, the easier it is for the body to do this. You can do this with a bigger drop, but it takes some getting used to. - Pace
Most runners will have a nice, prettier running motion on their faster, faster paced runs. The adjective nice here should be understood to mean closer to regular, optimum. This is because our body is trying to optimise the movement to use as little energy as possible to achieve a faster pace (in fact, this is the point of running, to cover a unit distance as fast as possible using as little energy as possible). So our body optimises and we run more regularly and beautifully when we run fast. This means that we land less on our heels and more in the middle or front of our feet, and a lower drop is better for that. The relative relationship is important. If you run with an 8mm drop and want a fast paced shoe, a 4mm drop is a good choice, but if you run with a 12mm drop, an 8mm drop can help you run faster, it’s unnecessary to choose a 4mm drop. (Otherwise, you just have to think about what happens at tempo changes (or starts and stops). You land on your toes when accelerating, on your heels when decelerating.
What is the best drop, what are the advantages of a higher or lower drop?
There is no such thing as a good drop. Everyone has a different drop, and most runners have different drops for different runs (length, speed, terrain).
There are many other characteristics of a running shoe that have an equally big impact on whether a running shoe works or not. It’s best to take a holistic approach and judge which drop is right for you, together with all the other characteristics. For example, zero drop might be right for you, but it’s also important that the shoe is stable and has a high cushioning. If you can’t find a shoe that has all of these, you can go for zero drop.
Should you change drop and if so, how?
Fundamentally, there is no universal truth to this either. There are runners who have the same drop in all their shoes because they like that particular drop, perform best in that particular drop and are least likely to get injured in that particular drop.
On the other hand, if a runner can afford to have more than one pair of running shoes and they have different drops because they are used for different distances or different types of running (e.g. tempo, gym, everyday), that is a good solution. The different drops put more stress on different parts of your body, move different muscles more, so you can keep them all in training and also get more rest.
When changing drops, be prepared that if the change is big (6-8mm difference), the new running shoe may be unusual and uncomfortable at first, and you may not perform well in it on your first runs, or you may even experience pain.
What else can help you judge the drop
The following may be just interesting, but they are also logical and worth considering when looking for running shoes based on drop
- Popularity
Higher drops are becoming more popular, while lower drops are selling fewer running shoes - Terep
As the drop increases, the proportion of trail shoes among all running shoes decreases. At zero drop, roughly 50% of running shoes are trail running shoes, at high drop only 20% of shoes are trail running shoes. - Foot height
This is probably the easiest to see logically, a higher drop also means a higher average sole thickness on the grand average, but there are exceptions. - Weight
As a result of the previous, a higher drop usually also means a higher weight, but luckily this is just an average, there are exceptions.
