The most successful climbing specialists come in different shapes and specializations. Climbers with very small physique such as José Rujano (48 kg), Nairo Quintana (58 kg), Roberto Heras (60 kg), Alberto Contador (61 kg) and Gilberto Simoni (58 kg) thrive when the climbs reach dizzying heights and incredibly steep slopes where their low weight makes them more efficient and able to put in repeated acceleration runs. Their endurance also makes them good stage race specialists. Marco Pantani, champion of the 1998 Tour de France, was able to make attack after attack to quickly tire out his opponents.