Zwift and smart trainers

For a few months now I’ve been trying to persuade myself to buy a new smart trainer and start riding on Zwift, the internet cycling social platform. So last Tuesday 25th July I bought a Tacx Neo direct drive smart trainer and set it up on the spare bedroom.

It took a while to fit the sprockets from the Giant Defy to the cassette body on the trainer but once I realised it needed an additional spacer (I had 10 sprockets and the body takes 11) all went quite well except I get chain jumping on the 4th largest sprocket, the first separate sprocket after the block of 3 biggest). A smart trainer measures speed (mph), cadence (rpm) and power in watts. When linked to software it will display and record all this data.

I have joined Zwift which gives you a range of virtual locations to ride, at the moment various circuits if different length and terrains on a fictitious island called Watopia, various courses in and around London including the Surrey hills like Box Hill, and the Richmond USA world championship course from 2015. In addition there are a number of training workouts to choose from for everyone from beginners to top athletes.

I have joined three Facebook groups focused on group rides and races on Zwift. The Big Ring, based in Australia, runs a series of weekly races on Mondays and Thursdays. The Monday races are handicap events which in principle puts everyone on a level footing. Most races are for different categories of riders depending on their watts per kilogram measurement. This is calculated by dividing your Functional Threshold Power (FTP) by your weight in kilograms. FTP represents your ability to sustain the highest possible power output over 45 to 60 minutes. Generally speaking the figure used is 95% average power you can achieve going flat out for 20 minutes. Mines about 160 watts at the moment so my watts per kilogram (current weight 94 kg) is 1.7 w/k, not very good. For Zwift races this puts me firmly in the D category for riders under 2.5 w/k. The Big Ring handicap races even everyone up by assigning them a weight to enter into their Zwift profile before the race. Strong light riders have an increased weight and heavy weak riders like me are given a lighter weight to enter. At the moment my race weight is 78 kilograms! The highest is 220 and the lowest 58. My first race will be next monday.

In the meantime I did a steady paced 1 hour ride with another Facebook group, Ride On For Health, or RO4H. This was very steady and it got me used to riding in company, drafting and closing gaps. The illustration below is of me (my avatar is not a good likeness!) leading the group. It’s a good supportive group mainly focused on fitness and health and, where appropriate rehabilitation.  Zwift seems to simulate drafting and the gradients very well and you get a real feel for group riding and the tactics of racing. On this ride I got a bit carried away and around the 40 minute mark another rider, not in our group, came past and I jumped on his wheel gaping my group by about 15 seconds at one point. I dropped back fairly quickly and we all finished together as intended.