Race Pacing Plans: Best Bike Split vs Garmin Power Guide Strategy (By Lindsay Straughton)

Generally, there are 4 methods of race pacing for the bike leg of a triathlon:

1)    Level of effort aka watch your heart rate,

2)    Target average power,

3)    Target average speed, or

4)    Go hell for leather out of T1, run out of steam and finish by coming into T2 on your arse.

1 is handy if you don’t really have a target time in mind and want to be able to complete without too much pain. 2 more or less achieves the same but with a bit more data and science behind it (and we all know Coach Paul is a data geek!)

3 works if you have a finish time goal in mind, but is only really accurate on a flat course – it can be hard to achieve an average speed over an undulating course or where there are long flat sections followed by undulations (eg LakesMan).

and ain’t nobody wants to be using 4 as a pacing strategy!

The method I like to use and that I’m going to cover in the following blog, combines 2 and 3 by using tech to predict a finish time ahead of a race and then pacing the race according to the power required to achieve that finish time on the day.

Best Bike Split

Best Bike Split is a software tool designed to help optimize bike race performance. It uses advanced algorithms and detailed data inputs to create “pace plans” tailored to the specific conditions of a race.

By inputting data such as the bike I‘m using, my riding position, how much my bike and I weigh, my target average power, uploading the course profile and adjusting for weather conditions, BBS can simulate how I will perform on a given course. In short, it spits out my estimated completion time.

All quite clever!

But the feature I use most is the Power-Based Pacing Plan. Instead of telling it my target average power I tell it my target race time. The software generates a power-based pacing plan, guiding me on how to distribute my effort throughout the race to achieve the best possible time. This includes recommendations on when to push harder and when to conserve energy, splitting the course into segments and adjusting the target power for each according to the elevation profile and in theory, road conditions.  The file is exported to my Garmin where it appears as a “course” to navigate. Using the BBS widget, I can see on screen what power I should be doing on each segment vs what I’m actually doing. 

The advantage is that instead of trying to hit a constant 170W average for 3 hours, which inevitably means some segments are “harder effort” and some are “easy effort” (according to say elevation), it smoothes the level of effort out by making some segments harder (eg 200W on a climb) and some segments easier (eg 130W on a descent). 

I’ve been using it for almost 3 years now so I’ve done quite a lot of testing and playing around with it. I’ve done the same routes firstly using BBS and then again not using it, but hitting the same average power by the end of each ride.  I definitely find following the BBS segments easier than sticking to a constant average power and I’m less “tired” at the end using BBS.  Handy even if you only ever use it to hit average power on training rides.

Now golden question #1… how accurate is it in races?

Broadly speaking – pretty accurate!

I find that sometimes it under estimates how much power is needed on a climb and over estimates how much power is achievable (without spinning out) on a descent, so in reality it’s most accurate on flatter courses. But having used it for almost 3 years I’ve learned to adjust. I’ve more or less hit target time in every race. Where I haven’t hit target race time (IM Wales!) it was due to outside factors, but average power was also significantly down.

The downside is that it comes with a price.  Standard pricing is £15/month or £95/year.  In the past I’ve paid monthly but only subscribed for the months I race (eg June to September).  I justify it that I cancel my Zwift over summer 😂 Sometimes you can get discount codes, last year I found one that made it £62.50 for a year.

Which brings me on to Garmin Power Guide.

Garmin Power Guide

This is a relatively new feature and not available on all devices, it is however completely FREE.

So this year I’ve been giving it a bit of a test to compare it with BBS.

To begin with, it seems a little bit more basic:

1)    It doesn’t allow you to input your specific bike, only select whether your position is upright, low (drops) or aero. It does however allow adjustment for bike weight and pulls through the rider weight and FTP from your Garmin Connect profile.

2)    It doesn’t allow you to input a target race time, only target average power from which it estimates the completion time as a range to within 30 minutes (eg 2:30-3:00)

It still splits the “course” into segments and gives a target power for each which you then follow on your device much the same way as with BBS.

So golden question #2… how accurate?

Very.

Remember I said that BBS under estimates power needed for climbs and over estimates descents? Garmin Power Guide is much closer to reality. Over a hilly route I was able to hit the Garmin overall ride average bang on, whereas with BBS sometimes I’m 5-10% under.

Golden question #3… BBS or Garmin Power Guide?

I found Garmin easier to use than BBS, firstly because of the segment target power being closer to real life but secondly, I prefer the screen.  It uses the same screen as for indoor rides, which I use my Garmin for so I’m familiar with it. It’s also more customisable.  I have mine set to show current 3s power, segment average and segment guide and the screen handily turns green if I am hitting target or turns red if I’m not, with an ⬆️ or ⬇️to show which way.

It also shows ride average target and ride average current so I can see if I’m “up” or “behind” (which I think is what helped hitting the overall average, with BBS you have no idea if you’ve lost time!). I’ve added current cadence and HR, the latter so that if I’m pushing harder to catch up I can judge whether I’m going to hard and can back off.

I don’t think I’m quite ready to ditch BBS just yet though…..

I like that I can input my target finish and it gives me the average power I need to hit… I compare that to what Coach Paul recommends so that we can decide what’s realistic.  Once we’ve agreed a target power, I use that to programme Garmin and follow the Garmin Pace Guide on my device.  If Garmin get their finger out and add a goal time feature, I will definitely be using that as a standalone and ditching BBS completely!