Final answer:
In a custom triathlon, I would include rowing for a water-based and full-body workout, trail running for agility in unpredictable terrain, and mountain biking for a technically challenging off-road experience.
Step-by-step explanation:
If I were to create my own triathlon, I would choose sports that are not only physically demanding but also inclusive of different environments and skills. The first sport would be rowing, which is an intense full-body workout and allows for water-based activity just like swimming does in a traditional triathlon.
The second sport would be trail running, to incorporate an element of unpredictable terrain and the need for agility and coordination. The final sport in this customized triathlon would be mountain biking, to challenge the competitors with steep climbs, descents, and technical skills required for off-road biking.
Together, these three sports would test an athlete's endurance, strength, and ability to adapt to various challenges. Participants would need to train in different environments, mastering not only endurance and speed but also technical skills and mental toughness to successfully complete this triathlon.