If you're not already familiar with Training Stress Score (TSS)® and its components, check out Training Acronyms Defined before reading any further.
Now, with a basic understanding of TSS making its way into the recesses of your power-based training lobe, let's delve a little deeper into how you can make effective use of TSS beyond comparing one ride (or rider) to another.
Stress/Recovery Basics
Over time and with consistent training and proper recovery, your body adapts to the stress you inflict throughout your workouts. This adaptation results in increased work capacity and the ability to handle greater workloads, i.e. higher TSS's, in subsequent workouts.
But what happens if you don't properly increase your workload/TSS from workout to workout, training phase to training phase, year to year?
Move things along too quickly and your body breaks down. First comes overreaching (necessary and useful) and then overtraining (destructive and dangerous).
Progress things too slowly and you fail to reap the full potential of your training time, something that's especially costly for most riders who are on a limited training time budget.
But how do you determine the proper amount of TSS increase from week to week?
TSS Ramp Rates
By comparing one week's total TSS to another, you can fairly simply manage your weekly TSS growth by dividing each week's total by 7 (for the number of days in the week, on the bike or not) to get your average daily TSS per week (dTSS/wk).
Though not ideal examples, if you compare week 4 (163 TSS) to week 3 (263 TSS) below, you'd get dTSS/wk of 23 and 38, respectively, and a growth of 15 daily TSS points from week 4 to week 3.
Typically, a weekly ramp rate in the 6 TSS neighborhood (+/- 2 TSS) works well for most riders, so a weekly ramp rate of 15 TSS is not recommended but still useful for our needs here.
This too-fast ramp rate may explain why the following week actually declines a bit, perhaps due to too much residual fatigue hanging on from the prior week. And what of the following week? Off the bike entirely?
Now this rider's data is a ideal example of how you can derail your training by neglecting to consider your TSS ramp rate.
Calculating TSS Ramp Rate
Tweaking a commonly utilized formula (Previous Week's TSS + 6*rr) for our simpler purposes, we'll use a ramp rate (rr) of 6 TSS and week 4's total TSS of 163 TSS to get the following:
163 TSS + 6*6 = 163 TSS + 36 = 199 TSS
Had this rider progressed things in a more reasonable manner, week 4's TSS of 163 (23 dTSS/wk) would have more reasonably grown to 199 TSS for a daily average of 28 TSS and perhaps the apparent downward spiral could have been avoided.
Target TSS Ranges
Now the question becomes, "Where do I start?".
Diving into a plan with a scheduled TSS of 450 during the first week, and thus a daily TSS average of roughly 65 TSS, could be enough to crush one rider while under-challenging another.
A while back, Hunter Allen and Andrew Coggan mentioned accumulating data such that they could determine TSS ranges for cyclists of varying abilities in much the same way they determined Power Profiles for wide ranges of riders.
Nothing has surfaced yet, and while we could speculate for days on viable ranges, provide plenty of anecdotal, n=1 case studies until we're blue in the face, we'll instead wait and definitely update this article when Coggan/Allen's information comes to light.
In the Meantime...
In the meantime, base your plan selection on the obvious: training hours and target events.
You'll undoubtedly have to do a little trial and error over the course of your self-learning process, but as your self-knowledge base grows, you're sure to develop a deeper understanding of the training loads that stir positive adaptation.
It's then a matter of determining how high you can nudge those stress loads before you need a recovery week or before you simply need to scale things back in order to avoid burnout and eventually overtraining.
And remember, great cyclists are years in the making.
While you can set immediate and short-term goals, the best cyclists have developed their abilities over years and years of riding, whether through formal training, recreational riding or full-on racing.