Suunto 2.50.26 – Q4 2025 Release Notes

Sportsfreund

@DrSilverthorn „ In comparison to running or rowing, cycling uses less muscle, so local muscle fatigue usually occurs before cardiopulmonary exhaustion.“

hooram

This Q4 2025 Suunto update looks huge! The multisport focus is impressive—automatic transitions for Triathlon and SwimRun, circular multisport, and the new ZoneSense features will make training so much smoother. I also love the per-sport persistent settings and the improved optical HR algorithms—it should finally feel closer to chest strap accuracy. The navigation and sensor improvements are a nice touch too, and the demo mode is perfect for in-store use. Overall, seems like a solid upgrade for both casual and serious athletes.

Brad_Olwin

@DrSilverthorn I completely disagree! Zones will change for sports but HR Max is a single value, period! This is physiology.

maszop

I managed to initially test the new software in relatively poor weather. Calculating elevation gain in moderate winds finally worked very well. At least, during moderate winds.

And as I mentioned earlier, none of the bugs I’ve been reporting on for many updates have been fixed. Specifically, the inability to change routes during ascent/descent, the crazy breadcrumb, and the occasional lack of updating of the current position on the map.

Elmiuel

Hi everyone, thanks for your input. I’ll enter my maximum heart rate achieved in both sports, but I’ll configure different ranges for each discipline since certain muscles or physical qualities are more involved. Thanks for your contributions.

DrSilverthorn

@Brad_Olwin go back and read my original post. We are in violent agreement. That being said, using a single HRmax value for purposes of training load computation, when using multiple sports is suboptimal, and IMO ‘wrong’.

VoiGAS

@DrSilverthorn Its not the HRmax that is used for Training Load in my experience, its the zones - especially the thresholds. And those you can set per sport

BastMaSVSRS9PP

@DrSilverthorn agreed.

Heart-rate–based training load metrics rely on normalizing effort relative to a reference such as maximum heart rate, implicitly assuming that a given percentage of HRmax represents a comparable level of physiological stress. In reality, HRmax is sport-dependent, varying with muscle mass involved, body position, contraction type, and neuromuscular recruitment; most athletes reach higher maxima in running than in cycling or other seated sports. Applying a single HRmax across multiple sports therefore misaligns intensity zones, systematically under- or over-estimating load for at least one activity and biasing cumulative metrics like weekly or chronic training load. This error is not random but structural, making cross-sport load comparisons unreliable and increasing the risk of hidden fatigue. For multi-sport training, sport-specific HRmax values or preferably sport-specific thresholds are required for physiologically defensible load estimation.

jjpaz

@BastMaSVSRS9PP said in Suunto 2.50.26 – Q4 2025 Release Notes:

@DrSilverthorn agreed.

Heart-rate–based training load metrics rely on normalizing effort relative to a reference such as maximum heart rate, implicitly assuming that a given percentage of HRmax represents a comparable level of physiological stress. In reality, HRmax is sport-dependent, varying with muscle mass involved, body position, contraction type, and neuromuscular recruitment; most athletes reach higher maxima in running than in cycling or other seated sports. Applying a single HRmax across multiple sports therefore misaligns intensity zones, systematically under- or over-estimating load for at least one activity and biasing cumulative metrics like weekly or chronic training load. This error is not random but structural, making cross-sport load comparisons unreliable and increasing the risk of hidden fatigue. For multi-sport training, sport-specific HRmax values or preferably sport-specific thresholds are required for physiologically defensible load estimation.

Tell that to Coros and his “One HR zones for all”…

2b2bff

@BastMaSVSRS9PP said in Suunto 2.50.26 – Q4 2025 Release Notes:

Heart-rate–based training load metrics rely on normalizing effort relative to a reference such as maximum heart rate, implicitly assuming that a given percentage of HRmax represents a comparable level of physiological stress.

Possibly this assumption of percentage of HR max is used as the reference isn’t correct after all? If Suunto uses HR zones for training stress calculation, then those are the reference…