This issue had been reported by different users previously:
And I've recently experienced it with my Fenix 5S.
When I "pause" my commute ride at 8am and "resume" the same ride at 6pm, the calorie count throughout the workday was significantly higher than days when I "stop" each ride and create two separate recordings. The reason why I prefer the "resume" feature is to avoid too many short recordings.
I don't know what the underlying issue is, but there could be some kind of inaccurate coding?
Is this something that can be resolved?