What are the most frequent problems and pathologies that arise from cycling?

I- Postural problems such as lumbago, dorsal pain, cervical pain, leg heaviness, and cramps.
II- Knee pain and tendinitis.
III- Tendinitis, which is more related to the use of large developments than to other factors.
IV- Lesions caused by friction between the saddle and the perineum, such as boils and hygromas.
V- Common diseases such as viruses, bronchitis, and tendinitis.
VI- The so-called 'pájara', which is a feeling of exhaustion caused by physical effort.