My heart is pounding in my throat. I fling my right leg over the bike seat and almost fall down.
We’ve been mountain biking for five minutes.
Luckily, these start-up problems don’t take very long. My body quickly adjusts to the constant work-out and my heart pumps my blood around in a regular …

“Even though climbing these huge boulders is difficult, I have the feeling it makes me a lot less tired than just walking up through the forest”, I say. John agrees with me. But apparently we are not climbing fast enough, since our guide replies: “That might be, but we are …