The Russian localization could be better. Examples:
1) "Уменьшение ИМТ на 22,4 может уменьшить ваш фитнес-возраст на 1,5 года/лет".
This probably implies that decreasing the BMI to 22.4 may result in decreasing your fitness age by 1.5 year.
If so, the preposition "на" in "на 22,4 ..." is incorrect, because this means "by 22.4".
So for now the Russian version means: "Decreasing the BMI by 22.4 may result in decreasing your fitness age by 1.5 year", which makes absoltely no sense.
2) Just after my waking up in the morning my Garmin Connect "Body Battery" page reads: "С момента пробуждения ваш заряд Body Battery увеличился на [50, например]...".
I believe this implies:
"By the moment of your waking up your Body Battery charge has increased by [say, 50] ...". Not "since the moment".
If so, then the Russian version is incorrect, because it means "Since the moment of your waking up your Body Battery charge has increased by [say, 50]...", which a few seconds after waking up in the morning is meaningless.
Garmin! and the poor localization ...
Pitifully, Garmin Support Center form does not enable me to fill this message in, which is wierd.