Every Burst is assessed. Here's what we check.
The hard part of a routine was never the activities — it's the order, the timing and the durations. Our engine draws on 2,401 assessed activity pairings and 467 reviewed studies to check exactly that.
There's a lot of thinking behind those two labels on every Burst card — plus a growing pool of real data from Bursts that have actually been completed. These two scores are us doing that work, so you don't have to.
Every Burst gets two scores. One reflects quality and the other reflects difficulty — separate measures that work best when read together.
Quality score
How well the Burst is put together: the sequencing and the logistics. Expressed as a percentage with a label. Higher is always better.
Good· 73%Difficulty rating
How demanding a Burst is likely to feel. A gentle Burst and a difficult one can both score highly on quality, so this helps you choose something that matches where you're at.
Demanding· 5Quality: is this thing well built?
The quality score answers the questions most routine content never bothers with. Does the sequence of activities make sense? And has someone thought through the practical stuff — setup time, transitions, breaks?
Are the activities in the right order?
There are 120 ways to sequence 5 activities. With 10, there are 3.6 million. Our engine evaluates every pair of consecutive activities and rates how well they work together.
What works well together
Stretching after resistance training can help recovery. Creative expression after meditation can help concentration. The engine recognises which activities work better together.
What creates friction
Intense physical activity right after mindful eating, or deep introspection straight after high-energy cardio. The engine flags these so they can be avoided or buffered.
2,401 pairings assessed
Every pairing across 46 activities, plus setup, rest and transitions, has been rated — including recovery after higher-intensity activities and moving between physical and mental ones.
Will the timings actually work in practice?
Good sequencing isn't enough if the practical stuff falls apart. The logistics assessment checks whether the Burst has been timed realistically.
Setup and reset time
Each activity needs time to get ready and wind down. The engine checks whether enough transition time is built in, or whether you're expected to jump straight from one thing to the next.
Session length
Is each activity long enough to be worthwhile but not so long it becomes a grind? A 3-minute meditation may not justify the setup; a 90-minute one mid-Burst might be unrealistic.
Breaks & nutrition
For longer Bursts, pauses and meal breaks get checked. Stretches of more than 3 hours without a break are flagged; going 4+ hours without refuelling can affect energy and focus.
Poor
Significant issues. Likely to feel disjointed or impractical.
Fair
Some things work, but noticeable gaps in sequence or timing.
Good
Well put together. The sequence flows and logistics are realistic.
Very good
Strong across the board. Very few rough edges.
Exceptional
Everything lines up. The logistics leave nothing to chance.
Most Bursts in the library sit at Good or above. A lower score doesn't mean the Burst won't be enjoyable — it means the engine spotted areas where the structure could be stronger. Your experience may still be great; it just hasn't been optimised in the ways the engine looks for.
Difficulty: how hard is this going to feel?
Difficulty is separate from quality. A gentle Burst can be just as well built as a very difficult one. The difficulty rating helps you choose something that matches your energy, your experience, and how much you want to push yourself.
And remember, you're always in control while doing a Burst. You can shorten an activity, skip something, or take a longer break. The rating tells you what the Burst was designed to be, not what it has to be.
The engine checks six things across every Burst. Each one is rated independently, and the overall rating reflects the hardest point in the experience.
Session durations
Longer individual sessions are harder to sustain. A 15-minute yoga session feels different to a 60-minute one.
Total activity load
How much active time is packed in overall. 5 hours of activity is a bigger ask than 90 minutes.
Physical intensity
How much involves physically demanding activities like HIIT, resistance training and cardio.
Mental stillness
Sustained attention, like meditation and breath counting. Demanding in a different way.
Introspective depth
Inward reflection, like journaling and self-guided inquiry. Can be emotionally taxing, even when physically still.
Creative output
Expressive activities like making music or visual art. Sustained creative output can take more out of you than expected.
The label, the number, and what they mean together
The label = the crux
The label is based on the single hardest point in the Burst — the thing that'll push you most. In climbing this is the crux: the hardest move, and what the route is rated on. If the crux is beyond you, the rest doesn't matter as much.
The number = the stack
The number in brackets shows cumulative difficulty across all six checks. It tells you whether the Burst has one tough moment in an otherwise gentle experience, or whether the difficulty is stacked across multiple areas. A "Very difficult [4]" has one major crux and little else; a "Very difficult [12]" is relentless. Gentle and Manageable Bursts don't carry a number.
One thing worth knowing: the difficulty rating is calibrated for a healthy adult who may not be experienced in all the listed activities. If you already do HIIT three times a week, a Burst rated Demanding for physical intensity might feel easier to you. If you've never tried breath work, a Manageable Burst might feel harder than expected. The rating is a useful guide, not a guarantee.
Gentle
Calm, accessible, low-demand. Suited to most people.
Manageable
Some effort but well within reach. A good starting point.
Effortful
You'll need to work. Not one to drift through.
Demanding
This will stretch you in at least one area.
Very difficult
Peak challenge. Will probably push your limits.
Neither low nor high difficulty is better. A gentle Burst after a hard week might be exactly what you need; a demanding one when you're feeling strong might be exactly what you want. Either way, you can always adjust as you go — a Burst is meant for guidance and structure, not pressure to follow it perfectly.
A lot of thinking, distilled into two labels.
Behind them: sequencing logic, logistics checks, difficulty across six dimensions, 2,401 individually assessed activity pairings, and a growing pool of real data from people who've actually done them. And we won't bore you with what powers the 1,164+ activity guides in the rest of the app.
Now you know what the scores mean.
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