Frequently Asked Questions

Watta is a free AI-powered rowing workout tracker for iOS. It lets you photograph your Concept2 erg screen after any session and automatically extracts your workout data using AI OCR. Every session is scored with a proprietary 0-100 Effort Score that combines cardiac load, work output, pacing, and economy into a single number.

After finishing your workout, open Watta and take a photo of your PM5 screen. The AI OCR engine reads the display and extracts distance, time, average split, stroke rate, and interval breakdowns automatically. No manual entry, no Bluetooth pairing, and no extra hardware required.

Watta supports any Concept2 ergometer with a PM5 monitor, including the RowErg, SkiErg, and BikeErg. The AI OCR is trained specifically on PM5 screen layouts to ensure accurate data extraction across all three machine types.

Yes. Watta is completely free to download and use. There are no premium tiers, no paywalls, and no feature gating. Every feature, including AI OCR capture, Effort Score, heart rate zone analysis, clubs, squads, and Strava sync, is available to all users at no cost.

No. A heart rate monitor is optional. Watta tracks your workouts and calculates work output, pacing, and economy scores without one. However, if you do wear a heart rate monitor and enter your average and max heart rate, Watta unlocks the full Effort Score including Cardiac Load analysis and personalised Karvonen heart rate zones.

The Effort Score is Watta's proprietary 0-100 rating that captures how hard you actually worked during a rowing session. Unlike metrics that only measure distance or speed, the Effort Score combines four dimensions of performance into a single number that reflects true training intensity.

The Effort Score is a weighted composite of four components: Cardiac Load (up to 40 points, from your average heart rate as a fraction of heart-rate reserve, scaled non-linearly — or a conservative power-based estimate capped at 28 when no heart rate is recorded), Work Output (up to 35 points, average watts against a body-weight-scaled 150 W baseline with a logarithmic duration factor), Pacing (up to 15 points, split consistency across intervals with a negative-split bonus; a single piece scores 10) and Economy (up to 10 points, watts per stroke). The maximum possible score is 100.

Effort Score zones classify your session intensity: Recovery (0-25) for easy, regenerative sessions; Building (26-50) for aerobic base and steady state work; Training (51-75) for structured intensity and interval sessions; Peak (76-100) for race-pace efforts and maximal output. These zones help you balance hard and easy days across your training week.

Heart rate alone only captures cardiac stress. The Effort Score goes further by also accounting for the mechanical work you produced (watts and duration), how evenly you paced the piece, and your stroke economy. Two sessions at the same average heart rate can produce very different Effort Scores depending on your output and pacing.

Watta uses the Karvonen method to calculate five personalised heart rate zones. You enter your resting heart rate and maximum heart rate, and Watta computes zone boundaries based on your Heart Rate Reserve (HRR = max HR minus resting HR). This produces zones that are tailored to your fitness level rather than generic percentage-of-max estimates.

The Karvonen method is a heart rate zone formula that uses your Heart Rate Reserve (the difference between your maximum and resting heart rate) to set personalised zone boundaries. The formula is: Target HR = Resting HR + (HRR x intensity%). For trained athletes, Karvonen zones are significantly more accurate than simple percentage-of-max calculations because they account for aerobic fitness.

UT2 (Utilisation Training 2) is the foundation of rowing training, a low-intensity aerobic zone where you build your cardiovascular base. In Watta, UT2 corresponds roughly to Zone 2 on the Karvonen scale. Watta helps by showing you exactly where your heart rate sits relative to your personalised zones, so you can keep your steady state sessions in the correct intensity band rather than drifting too high.

Yes. Watta works without a heart rate monitor. You can still log workouts via OCR, track distance, time, split, and stroke rate, view pacing and economy scores, and compare sessions over time. Without heart rate, the Cardiac Load part of the Effort Score is estimated conservatively from power and capped at 28 of its 40 points; pairing a strap to the PM5 so heart rate shows on the screen unlocks the full range and the zone label, but it is not required to use the app.

Clubs in Watta are shared spaces for rowing communities. Any user can create a club, and once it is verified by a platform admin, members can join via an invite code or by requesting access. Club members appear on a shared feed and leaderboard. Each club can have up to three admins who manage membership and settings.

If you and your coach are in the same club or squad, they can see workouts you post to the club feed. You can also mark your coach as a close friend, which gives them access to more detailed training data. Workout visibility is controlled by your profile privacy settings.

Yes. Watta syncs your rowing workouts to Strava automatically. Once you connect your Strava account, each new workout you log in Watta is pushed to Strava as a rowing activity so it appears alongside your other training in your Strava feed.

Squads are sub-groups within a club. They let you organise members into smaller training groups, such as a novice squad, a senior squad, or a HYROX training group. Each squad has its own feed view so members can focus on the workouts most relevant to their group.

Watta collects the workout data you log (distance, time, split, stroke rate, heart rate), your profile information (name, email), and optional social data (club memberships, follows). Photos taken for OCR are processed to extract workout metrics and are not stored permanently. Full details are available in our Privacy Policy.

No. Your workout data is not sold or shared with third-party advertisers or data brokers. If you choose to connect Strava, your workouts are synced to your Strava account at your request. Club and squad members can see workouts you share on those feeds, based on your privacy settings.

Yes. You can request full account deletion at any time by contacting support@polarindustries.co. When your account is deleted, all associated personal data and workout history are permanently removed from our systems in accordance with GDPR requirements.