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Home / Training / Functional threshold power: what it is and how to boost it

Functional threshold power: what it is and how to boost it

Former 70.3 world champion Holly Lawrence's coach John Feeney, of trainSharp, explains all you need to know about functional threshold power, including how to calculate it

Coach John Feeney with 2016 70.3 world champ Holly Lawrence

For triathlon and other endurance sports, having a well-developed aerobic engine is a prerequisite for successful performances. However, being able to utilise the highest percentage of your aerobic capacity for a prolonged period of time is arguably a more important determinant of success.

Your functional threshold power (FTP) is closely correlated to the lactate threshold and represents the highest power output you can sustain for 1-hour without fatiguing. Over recent years, FTP has been used a key performance benchmark in both cycling and triathlon from which to measure training effectiveness and predict future performance.

How to calculate your functional threshold power

FTP can be determined using a 20-minute test protocol, a sustained 60-minute effort or by blood lactate profiling. The 20-minute test provides an estimate of your functional threshold power whereas blood lactate profiling takes away the guess work and accurately identifies your body’s response to exercise at different work rates. In addition, it also identifies both lactate thresholds, which is important from a coaching point of view.

In the spring the focus will switch away from winter base training to more race specific efforts with a focus on building lactate tolerance, power and race pace efforts. Whatever method you use to determine your FTP, being able to increase it will be key to improving your performances.

How to boost your functional threshold power

Holly Lawrence, the 2016 Ironman 70.3 World Champion has been coached by trainSharp over the last couple of years. We have been working with Holly to develop several areas of her performance including pushing up her functional threshold power.

What is bike threshold training?

Whilst there are no shortcuts to success, we have one session that will really help boost your threshold power, increase your tolerance to riding at these higher work rates and improve your race performance. To start with, if you don’t already know what your FTP is then you’ll need to estimate it using one of the self-tests mentioned above. This is a tough session and you’ll be training outside of your comfort zone!

Try starting with a 10-minute incremental warm up progressing through zones 1, 2 and 3.

Finish with 5 minutes easy spinning then into the efforts alternating 2 minutes spent above your FTP then aiming to recover for 2 minutes at or just below your FTP.

Aim for 2 reps, recovery for 5 minutes then go for another 2 reps.

Finish with a 10-minute warm down.

Aim to increase the numbers of reps by 1 each week over a period of 6-weeks.

The first time you ride this session it will feel very tough, perhaps bordering on an all-out effort by the end of each interval. Make sure you are well fuelled, hydrated and suitably motivated for a tough session.

Try not to spike the power in the first few seconds of the lifts, aim hold the power as consistent as possible whilst maintaining a nice, smooth cadence. After a few weeks, your body will adapt to the increasing training load. These adaptations include an enhanced muscular ability to mobilise fat for energy production and greater oxygen delivery to the muscles thanks to an increased network of capillaries.

In addition to these shorter, higher intensity sessions, Holly’s training also includes sustained efforts just below FTP. These sessions are more race specific and geared towards longer steady state/threshold efforts. Pacing skills are essential for optimising performance over the longer distance triathlon events and these longer interval sessions provide a great opportunity to practice.

Whilst training at, or just above your FTP is hard, it will reap rewards! Try to avoid the temptation to suddenly start increasing the duration of your higher intensity training sessions. Although you may feel this is important for building confidence, it’s likely to increase your recovery time and expose you to an increased risk of injury.

Instead, you should take a lead from elite athletes like Holly Lawrence by focusing on making your sessions more specific and gearing them towards longer steady state/threshold bike efforts. Pacing the longer bike efforts are likely to present more of a challenge and so you should consider investing in a power meter and incorporate performance testing or self-testing into your periodised training plan.

TrainSharp coach John Feeney holds a Masters in Sport Science, with a specialisation in endurance performance, heat acclimatisation, running and triathlon, and conducts their in-house performance tests and assessments, and also coaches Holly

For more information on trainSharp coaching and fitness testing packages email info@trainsharpcyclecoaching.co.uk or call us on 0044 (0)1892 577802.

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Highlights of the February 2018 issue include: 25 ways to fire up your motivation; races still to do; how to kickstart your training in 8 weeks; how to build a winning triathlon body – whatever your age; and all the latest tri kit tested and reviewed, including road bike shoes, transition bags and 3 tri bikes from the USA

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