Bar charts are faster and more accurate to read on a smartwatch than the radial ring displays that Garmin, Apple and Samsung use for goal progress, according to a review of 51 scientific studies.
- In controlled perception tests, bar charts produced the shortest reading time (318 ms) and the lowest error rate (24%) for goal-progress checks on a smartwatch, ahead of radial bars (397 ms, 26%) and plain text (503 ms, 31%).
- A second study of 32 participants found bars fastest across three exercise-data tasks, although radial bars were slightly more accurate for estimating completion percentages and exercise duration.
- Participants rated the radial designs as more attractive despite their worse performance, which the authors suggest explains why manufacturers default to them.
- In one study, 76% of long-term Fitbit users had never used their historical data to look for trends, and their own estimates of daily step counts were out by roughly 20%.
- Across several studies, showing people they missed a goal made some avoid the app rather than train harder. Arthritis patients using Fitbit data with their physiotherapists reported guilt rather than motivation when targets were missed.
- An experiment with 273 fitness tracker users found that AI-written summaries of activity data scored higher than charts for comparison-based reflection and engagement, though the researchers warned of patronising framing and factual errors.
What it means for watch design
Every major watch platform uses rings for daily goals, and the evidence says that choice favours how the watch face looks over how quickly an athlete can read it mid-session. A bar would give a faster and more accurate read of goal progress, but the rings remain the default on Garmin, Apple and Samsung.
The historical-data finding is more useful. Watch apps are built to check today’s numbers rather than spot patterns across months, so years of wearing a tracker did not translate into accurate self-knowledge for most users in the study. The authors also found that how a missed goal is framed matters more than whether it is shown, since guilt pushed people away from their data rather than towards their training.
Quick answers
Are activity rings less accurate than bar charts on a smartwatch?
Yes. Controlled studies found bar charts are faster to read and produce fewer errors than radial ring displays for goal-progress tasks. Radial designs are rated as more attractive, which is likely why manufacturers prefer them.
Can showing missed goals put athletes off using their watch?
Yes. Several studies found that negative feedback, such as showing unmet targets, made some people avoid checking their app rather than training harder. How a missed goal is framed matters more than whether it is shown.
More research on wearables and training is in the Sports Science hub.
Last Updated on 31 October 2026 by tfk the5krunner
Small things I always use
- Garmin 90-degree charging adapter: Charges your Garmin from any USB-C cable. Essential when travelling. I use one.
- Body Glide: The blue anti-chafe stick swimmers and runners carry. I use it.
- Speedo earplugs: Fewer ear infections and no cold-water dizziness. I use them.
- Dryrobe Advance: My winter changing robe for open-water swims. I use one. A cheaper option is the AONYIYI changing robe.
- Maurten: Race fuel that stays easy on the stomach. I use them.
- Beet It Sport nitrate shots: Beetroot shots I take in the days before a race. I use them.
- Garmin charging puck: The quickest way to top up before a session. I use one.
- Injinji: Toe socks that stop rubbing, so you run more. I use them.
- Ultimate toe protectors: Stop black toenails on long runs. They work. I use them.
- Compressport R2 v2 calf sleeves: My calf sleeves of choice. I use them.
- Cellucor C4: My pre-workout before hard sessions.
- TPU tubes: Schwalbe Aerothan, Tubolito and Pirelli SmarTube. Light, tiny spares. I use all three.
- G8 insoles: Adjustable insoles that are good. I use them.
- Cycplus Cube: A 97g electric pump that gets a road tyre rideable in two minutes. I carry one. 5% off with code THE5KRUNNER.
Watches and sensors
- Polar H10: My daily driver for waking HRV.
- Polar Verity Sense: My backup arm-worn HR sensor.
- Nomad bedside charger: Charges my iPhone and Apple Watch overnight. I use it, and many of their bands.
- Train.Red: The best muscle oxygen sensor I’ve used.
- Tymewear: Accurate heart rate and reliable ventilatory zones. I use it to pace endurance rides over an hour.
- Garmin Forerunner 970: A pro-grade triathlon watch. I use this.
- Apple Watch Ultra 4: My daily smartwatch. No phone needed on rides.
- Garmin Fenix 9 Pro: I’ve just bought one.
On the bike
- Continental GP5000 for everyday riding, and Aero 111 on the front for special occasions.
- Helmets: Specialized S-Works Evade 3 for road riding, and Rudy Project Wing for TT-style races. I use both.
- Ravemen FR300: A front light that mounts under your Garmin or Wahoo. I use one.
- Wahoo TRACKR Radar: I use it on one bike and Varia on the other. They perform the same.
- Garmin Varia RTL515: Radar that warns you of cars from behind. I use this model.
- Wahoo ELEMNT Roam 3: The bike computer that’s easy to use. I use mine on most rides.
- Favero Assioma Pro RS2: Accurate power pedals that swap easily between bikes. I use this model.
Home and indoor training
- NPE Runn: Makes my basic treadmill smart, sending more accurate speed and distance to my watch and Zwift. I use it.
- Google Wifi: Keeps Zwift connected in my pain cave. I use it.
- Apple TV 4K: Zwift on the big screen. I use two.
- Google Nest Doorbell (wired, 2nd gen): My video doorbell, running in both Google Home and Apple Home. I use it.
Health, recovery and sleep
- FreeStyle Libre 3 Plus: Shows how my blood sugar responds to diet.
- hDrop: Measures my sweat loss in summer and indoors.
- Fourth Frontier Zone: Checks my heart under load in hard sessions.
- Oura Ring 5: My partner’s recovery tracker of choice.
- Eight Sleep: A cooling mattress cover my partner and I use nightly.
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Written by real people, with AI assistance. Fact-checked and verified for originality. See the Editorial Policy. FTC: Affiliate Disclosure — some links pay commission. As an Amazon Associate, I earn from qualifying purchases.
tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. See the gear tfk uses. ID
