High-Intensity Interval Training (HIIT) is a form of training whereby you work at an intense level for a prolonged period of time with very little rest. The basic idea is that by working at such an intense level, you can maximise the efficiency of your workout by achieving greater benefits in a shorter time. We’ve teamed up with personal trainer and Noom UK consulting fitness expert Rob Brennan to give you the low-down on why HIIT training is beneficial for runners.
Basic running training plans often focus on LSD training (Long Slow Distance). This puts the emphasis on quantity, encouraging runners to conduct their runs at a steady pace, while gradually building up the requisite mileage for their target race.
The above certainly gets many people through events, and they probably see some speed improvement over time as general fitness improves, but performance would soon plateau. For a competitive runner, or someone looking to really fulfill their potential, it would not be optimal to train this way.
Thankfully, with the knowledge we now have of strength and conditioning, even non-competitive runners are becoming aware of the benefits of weight training, interval training and HIIT. Here is why HIIT is so good:
An efficient runner will have a long stride and their feet will strike the floor in the mid to ball of the foot, using the calves in particular to spring from stride to stride. HIIT usually involves a lot of calf-intensive exercise, such as jumping, skipping, sprinting or hopping. All of these will strengthen and tone the calves, facilitating those long strides and leading to greater and more consistent power output from the calves.
Ensuring the HIIT workouts have a plyometric element (most do), enhances the ‘springiness’ of the runner’s limbs and improves power output, boosting fast-twitch muscle fibres for speed of leg movement. The repeated jumping and springing involved in HIIT (when built up over time and done with correct form and care) will strengthen connective tissue and bolster joint stability, meaning runners are more robust and less likely to sustain injuries to the knees, hips and ankles while running.
All athletes benefit from an improved lactic acid tolerance (lactic acid is a waste product of hard exercise that makes your muscles burn and ultimately stop working). When training at higher-intensity levels, more lactic acid is produced, which over time improves the athlete’s tolerance to it. This means that they are less affected by the lactic acid produced when they endure strenuous running sessions, so can run harder and longer without feeling the burn.
As well as the benefits of improving strength, power and muscle development, HIIT is an intense cardiovascular workout too. Heart rates will most likely reach a higher max level than in any endurance running event, therefore strengthening the heart. This means runners will find it easier to push harder during lower-intensity activities (such as running). Lungs are also pushed to the limit during HIIT, due to the demand from your aching muscles for oxygen. Based on the same overload principle, this improves their efficiency and capacity, allowing a higher level of performance when running.
HIIT, as already mentioned, is one of the best ways to burn body fat. Reducing body fat has the obvious benefit to runners of making them lighter and leaner and therefore faster.
So, in summary, LSD training will improve endurance and lead to a (limited) improvement in times. HIIT will boost muscular power output and efficiency, increase fast-twitch fibres, stabilise and strengthen joints, strengthen the heart and lungs and improve lactic-acid tolerance, all while promoting a lean physique. Talk about a win!
Of course, no runner should neglect ‘getting the miles in’ and must maintain at least one ‘long’ run per week, where ‘long’ relates to a significant amount of the event distance, or even an equal or greater amount if it is a shorter run like a 5K or 10K. However, HIIT should feature at least twice per week, and can be done as many as three or four times per week. Recovery is important, and will enhance your ability to work hard more often, so refuel as soon as possible afterwards with a high-protein shake or snack with some carbs to quickly replenish muscular glycogen stores and maximise muscle gains.
Sample workout: 31 minutes with a 5-6 minute warm down
As with any workout, it is important to start at a lower intensity, build to a peak and then finish with stretching. This is a challenging workout, so additional rests must be taken if required and, if a particular exercise is too demanding for the participant, then they must judge this for themselves and reduce the intensity and/or the frequency of it to suit their own fitness level.
Do each exercise in each circuit for 35 seconds with no breaks. Do each circuit three times, increasing the pace each time. The increases in pace are optional, and circuits should, of course, be done at a pace or intensity level to suit the participant.
Warm-up to moderate circuit (8 mins 45 secs)
60-second break (basic) or 60-second jog (advanced)
Main Circuit 1 (10 mins 30 secs)
60-second break (basic) or 60-second jog (advanced)
Main Circuit 2 (8 mins 45 secs)
Warm Down Stretch (5-6 mins)
Stretch all main muscle groups for at least 30 seconds, including quads, glutes, hamstrings, calves, groin, shoulders, chest, upper back, lower back and neck.