Living life in the fast lane; the truth about training for speed

Over recent years, a growing body of evidence has been accumulating that once you’ve reached a good base level of fitness, the way you manipulate your training intensity is the key to making further progress. There are an infinite number of ways to add speed/intensity to a training program. This can be achieved by many, many permutations of a number of variables including:

•             The intensity of a workout or interval.

•             The workout/interval duration and numbers of intervals.

•             The number of intense sessions per week and ratio of intense to low-intensity (zone 1 training).

Needless to say, it’s impossible to make definitive recommendations for everyone. Firstly, what works best will vary according to an individual and his/her event/distance. Secondly, the recommended balance of these factors will change as fitness levels change, and at different times of the season. What we can do however, is to look at studies to see what kind of protocols have been tested and how effective they are.

Is less more?

A 2017 study by a team of Danish scientists looked at the frequency of added high-intensity speed endurance training⁽¹⁾. In particular, it sought to establish whether speed-endurance training performed every second day was more effective than performing it only half as often. Eighteen male and 14 female trained runners completed 20 sessions of training. However, the runners were split into two groups:

•             Speed-endurance training every other day.

•             Speed-endurance training every fourth day.

The speed-endurance protocol was based on high-intensity intervals. During the these sessions, the subjects first warmed up by running 1.5kms gentle then performing running, and sprint-specific exercises such as butt kicks, skips, and skips for height), and dynamic stretches (e.g., leg cycling, leg drives, and jump squats).

Following this the subjects performed all-out 30-second running bouts each separated by 3.5 minutes of rest. The ‘every other day’ group performed twelve 30-second repetitions on day 1 and day 5 and eight repetitions on day 3 and day 7, during an 8-day block. The ‘every fourth day’ group performed ten repetitions on day 2 and day 6 during an 8-day block. The difference in protocols was to ensure that the every other day group were able to spread the workload a little more evenly during each 8-day block

The key findings were that just ten speed endurance training sessions improved short-term exercise capacity and 10km performance of the runners – regardless of the frequency of training (see figure 1). If anything, the lower-frequency training resulted in greater performance improvements. And while adding a further ten sessions further improved sprint capacity, it didn’t result in any extra benefits for 10km performance. This is an important point; the runners in this study were well trained with excellent levels of fitness. Doubling the frequency (and workload of high-intensity training) produced no extra benefits – possibly because it didn’t allow for adequate recovery – something that less capable athletes should bear in mind.

Figure 1: 10km performances after ‘every fourth day’ speed-endurance training