Garmin vs WHOOP vs Polar: Which Smartwatch Estimates VO2 Max Most Accurately?

TL;DR

Garmin and WHOOP provide rough VO2 max estimates, but this limited comparison does not establish a definitive winner, while Polar showed a weaker correlation with laboratory results. Garmin reached a 0.85 correlation from roughly seven observations, WHOOP often overestimated values, and Polar reached 0.5. Read on to understand each device’s performance, the study limitations, and why laboratory testing remains the most accurate option.

Transcript

Normally, if you want to measure your V2 max, you have to use a mask like this connected to a very expensive device that measures things like your oxygen consumption. Now, for most of us, this is not something we can do on a day-to-day basis. Now, luckily, given the importance of your V2 max for your lifespan, your health span, and also your fitnes... Read More

Key Insights

• WHOOP is a reasonable indicator of general cardiovascular fitness because its estimates were clearly correlated with laboratory reference measurements. However, most WHOOP observations were above the perfect-agreement line, indicating that the strap tended to overestimate VO2 max for many participants.
• WHOOP can differ substantially from a laboratory result for an individual. One male participant had a reference VO2 max of approximately 54, while WHOOP estimated about 64, although another participant received an estimate that matched the reference measurement perfectly.
• Garmin showed a correlation of 0.85 with the laboratory reference values in the available sample. The pattern suggested that Garmin could provide a rough estimate of VO2 max, but the analysis included only about seven data points, creating considerable uncertainty.
• Garmin sometimes underestimated VO2 max in this dataset. The participant with the highest available Garmin-matched reference measurement had a laboratory value of approximately 60 or 61, while Garmin estimated the value at 56.
• Polar showed a correlation of 0.5 with the reference measurements, which was lower than the observed correlations for WHOOP and Garmin. The presenter suspected that much of Polar's correlation resulted from its strong separation of male and female estimates rather than accurate individual ranking.
• Polar did not reflect important overlaps between male and female laboratory results. Its estimates placed every man above 60 and every woman below 55, although the reference data included a woman at 60 and a man at approximately 52.
• Laboratory testing is the best option when an accurate individual VO2 max measurement is required. Wearable estimates sometimes matched the reference but could also be materially too high or too low, with the direction of error appearing to vary partly by brand.
• Wearable VO2 max trends may be more informative than isolated values or comparisons between people. A large change may reflect improving cardiovascular fitness, but a difference of only a few points between friends does not reliably establish that one person is fitter.

Questions & Answers

Q: Which smartwatch estimates VO2 max most accurately: Garmin, WHOOP, or Polar?

The limited results do not establish a definitive winner. Garmin showed a 0.85 correlation but had roughly seven matching observations, while WHOOP had more complete data and a statistically significant relationship with laboratory measurements. Polar showed a weaker correlation of 0.5.

Q: How accurately does WHOOP estimate VO2 max?

WHOOP estimates generally followed the laboratory results, with people who measured higher in the lab also tending to receive higher WHOOP values. However, WHOOP overestimated VO2 max in most observations. One participant measured around 54 in the laboratory but received a WHOOP estimate of 64.

Q: How accurately does Garmin estimate VO2 max?

Garmin produced a correlation of 0.85 with laboratory reference measurements, suggesting it can provide a rough estimate. It sometimes underestimated VO2 max, including reporting 56 for a participant whose laboratory value was approximately 60 or 61. The Garmin comparison contained only roughly seven observations.

Q: How accurately does Polar estimate VO2 max?

Polar produced a correlation of 0.5, which was weaker than the observed Garmin and WHOOP relationships. Polar placed every man above 60 and every woman below 55, despite laboratory results including a woman at 60 and a man at approximately 52. Its apparent correlation may therefore have depended heavily on separating male and female participants.

Q: Can a smartwatch replace a laboratory VO2 max test?

No, a wearable cannot replace a laboratory reference test when an accurate individual VO2 max measurement is required. The devices sometimes matched laboratory results but could also estimate materially higher or lower values. They are better suited to indicating broad fitness levels and patterns.

Q: Can wearable VO2 max estimates track fitness changes over time?

Wearable estimates may help track broad trends, especially when the reported change is substantial. The precise value can still be inaccurate, and changes may also appear in metrics such as resting heart rate. A wearable VO2 max estimate should therefore not be treated as the only fitness indicator.

Q: Can you compare VO2 max estimates between friends using wearables?

Small differences between friends do not reliably show that one person is fitter than another. The comparison found meaningful individual errors, including both overestimation and underestimation. A laboratory reference test is needed for a more dependable personal comparison.

Q: What were the limitations of the Garmin, WHOOP, and Polar comparison?

The analysis used data from 16 trained athletes, with fewer matching observations for Garmin and Polar. Garmin had only roughly seven data points, and the dataset contained few low VO2 max values. Participants also used their devices normally instead of following brand-specific testing protocols.

Summary & Key Takeaways

• Definition: Laboratory VO2 max testing uses a mask connected to an expensive device that measures oxygen consumption.

• Who: Rob is a post-doctoral scientist specializing in biological data analysis.

• Number: The comparison used data from 16 trained athletes, including men and women.

• Compare: WHOOP had the most complete dataset and showed a statistically significant overall relationship with laboratory measurements.

• Number: One participant measured around 54 in the laboratory, while WHOOP estimated 64.

• Number: Garmin produced a correlation of 0.85 from roughly seven matching observations.

• Compare: Garmin reported 56 for a participant whose laboratory VO2 max was approximately 60 or 61.

• Number: Polar produced a correlation of 0.5 with laboratory reference measurements.

• Compare: Polar placed every man above 60 and every woman below 55, despite overlapping laboratory results.

• Tool: Excel, coding, plots, and correlation metrics were used to compare wearable estimates with laboratory reference values.

• Definition: Wearable VO2 max values indicate broad fitness patterns more reliably than precise individual measurements.

• Tool: A laboratory reference test is the best option when an accurate individual VO2 max value is required.