Power for Triathlon: Blog 1/3

Training to power: An overview for triathletes.

With the improvements and advancing technology in the cycling world, power meters are fast becoming a mainstream addition to a serious triathletes machine. The benefits of training and racing to power are very applicable to cycling in triathlon, particularly long distance events.

Over this three part blog we will look at the features; benefits; options and application of Power into your training and racing plan.

About power and power meters

A power meter is able to provide you with instant feedback about the amount of physical effort you are exerting to move your bike. Power is measured in Watts and is a measurement of the force exerted from your legs to your bike’s drivetrain per second.

Power is able to show you how hard you are working at that point in time – the higher your power output is (in relation to your power zones), the harder in general you are working. When compared to heart rate, power readings are instant whilst heart rate is lagged and responds to the demands of that exertion. This allows power to be a more sensitive and responsive tool when riding a bike compared to heart rate. Consider a stretch of road with some hills and different surfaces. It will be easier to pedal downhill and over smooth surfaces than uphill and over rough surfaces. A power meter will tell you how much power you are putting through to the bike in each case, whereas the heart rate will be slower to adjust as your cardiovascular system reacts to the demands of the course.

The effects of aerodynamics and friction are so much more significant in cycling than in running and bike courses are so varied that power output required to maintain a certain speed will vary so much throughout a bike course. Consider the Busselton Ironman bike course – there are smooth patches of road, rough patches, sections of head and tail wind as well as slight inclines and declines. When riding through each of these areas, an athlete riding without power will find their target heart rate drift as well as their speed varying greatly. An athlete riding to power will simply ride to their target power zone the entire time.

Power and triathlon

Just like heart rate zones, an athlete can train to power zones to improve their performance. Threshold power can be determined just like running critical velocity or threshold heart rate can. From here, an athlete can then know what power zones they need to ride in to get the most optimal training and in term maximise their race performance. On race day the benefits are similar as an athlete knows what power zone they need to ride to throughout the race.

The benefit of power meters in triathlon is huge, and on race day power readings are arguably more beneficial to all triathletes than cyclists in a road race. This is because so much of a triathlete’s training and racing is done as individual efforts compared to road cycling where much almost racing is in groups. If you are able to know how hard to ride by yourself you will be in the best position possible complete the bike leg at an optimum level. In doing this, your run and therefore your overall race result will also benefit.

In part 2 Tom will talk about types of Power Meters and pro’s and con’s of each type…….


Thomas Bruins is a professional athlete and former 2012 and 2015 Oceania Professional Duathlon Champion as well as mutliple state Athletics and Duathlon champion. Tom is a qualified Engineer and Triathlon Coach who specialises in skill and performance consulting for triathlon. He can be contacted via email triathlon@frontrunnersports.com.au 

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