Summary of Reddit Comments on "Runalyze"

Accuracy and Predictions

• Runalyze is generally perceived as more accurate in predictions compared to Garmin for various distances. It is noted to be better for 5k, 10k, and half marathon time predictions, while Garmin is believed to be more accurate for shorter distances like 5k and 10k.
• Runners have noted how Runalyze is more pessimistic or conservative in its predictions, which can be seen through examples like a prediction of 3:38 on Runalyze compared to 3:24 on Garmin for a marathon.
• Marathon predictions on Runalyze can be skewed if consistent long runs are not done over the past 6 months. Marathon Shape calculates theoretical best races based on VO2 max and weekly mileage/long runs.
• VO2 max numbers can vary between Runalyze and Garmin, with Runalyze typically providing lower estimates. Users mention it's more about the trend than the actual number when it comes to VO2 max.

Usefulness of Metrics and Tools

• Users find metrics like % Fitness, Training Stress Balance, Workload Ratio, and Race Time Predictions on Runalyze to be valuable for tracking improvement and predicting race performances.
• The Analysis tab on Runalyze provides a good overview of training volume and paces. It allows for comparisons between different runs to see improvements over time.
• Some users find Runalyze to be complicated and require manual input for accurate results, especially in excluding runs that may skew data.
• Runners can adjust correction factors in Runalyze to improve predictions and ensure they are using reliable data for their metrics.

Challenges and Suggestions

• Some challenges with Runalyze include difficulty in excluding hilly runs, the need for proper training calibration, and the impact of cross-training on metrics.
• Users have encountered issues with mismatched pacing and heart rate affecting their VO2 max calculations, leading to lower than expected numbers.
• Runners have suggested properly setting heart rate zones, editing activities, and adjusting correction factors to improve the accuracy of predicted race times and VO2 max calculations.

Overall, users find Runalyze to be a valuable tool for tracking performance, predicting race times, and analyzing training data. It offers insights into fitness trends and can be adjusted for more accurate predictions based on individual training patterns and race performances.