Relationships between rating-of-perceived-exertion- and heart-rate-derived internal training load in professional soccer players: A comparison of on-field integrated training sessions

1. Campos-Vazquez, M.A.
2. Mendez-Villanueva, A.
3. Gonzalez-Jurado, J.A.
4. León-Prados, J.A.
5. Santalla, A.
6. Suarez-Arrones, L.