Q: "A mountain biker rides up a steep embankment and clears the top with great height." Does this mean that "The biker is coasting down hill."?
A: no

Q: "a tan dog running through the grass with the background blurry" Does this mean that "The dog was running towards their home."?
A: it is not possible to tell

Q: "A man is weightlifting with a kettlebell in a gym." Does this mean that "A man is lifting with a kettlebell in a gym."?
A: yes

Q: "A man on a bicycle jumps over jagged rocks amongst tall pine trees." Does this mean that "The man on a bike is wearing a helmet."?
A:
it is not possible to tell