What is Power?

Power is energy over time and is measured in Watts units. It is a product of your cadence and resistance level. Training with Power is only available in cycling and requires power sensors equipped bikes. Power is the work output, meaning how much effort you put while pedaling the bike, in each second. 

When training with Power, it is important to track Watts over time. Measuring the highest Watts output doesn’t reveal your real performance abilities. You need to check what is the highest Watts output you can sustain over time.

Spivi allows you to see your Power performance over time (last 30 days, last 90 days, last 180 days, and last year) in the My Workouts section of spivi.com, under Trends.

FTP Functional Threshold Power (FTP) is the maximum average wattage that one can sustain during a 60-minutes time trial on a flat road. Training with %FTP is a key element in any power-based cycling training program. Training with % of FTP allows members to train based on their fitness abilities. To estimate your FTP score, you should conduct FTP test.  

W/Kg Another way to measure Power is by calculating how much weight in Kg we can move to generate the Watts. To do that, you simply divide Watts in your weight in Kilograms. A cyclist weighing 190 pounds (86 kg) will need to generate more Watts than a 110 pound (50 kg) cyclist to maintain the same speed when using the same resistance. If you check their W/Kg, you'll be able to compare their power outputs.

To measure your power output, you can divide your FTP score with your weight in Kg. The result is the W/kg output of your FTP (maximal average power output over an hour).  

Kilojoules (Kj) A kilojoule is a measuring unit that let us know how much energy was expended over a certain period. Joules are an international standard unit of work/energy. 1 Watt = 1 joule applied for 1 second. 1000 joules = 1 kilojoules (KJ) Kilojoules = watts X seconds / 1000   KJ can also be converted to Calories (Kcal), to display the burned calories during a workout: 1 kJ = 0.2 Calories (Cals) 1 Calorie = 4.2 kJ