In sub-zero winter temperatures, these trainees at a derelict army base outside Beijing wake before dawn to practice martial arts and evasive driving. It’s all part of preparations to provide security for the growing number of Chinese businesses investing in turbulent regions of Africa and the Middle East. Under the instruction of former Portuguese special forces bodyguard Marco Borges, the 40-strong group, most of whom have military backgrounds themselves, take part in a grueling regimen.