While we are working or living in severe environment, the internal pressure changes of functional garments, the resistance from clothing and the thermal insulation for individual will lead obviously changes of our workload, heart rate and metabolic rate. Working in extreme circumstances and dressing pressure garments make workload increased significantly which limit people's ability to accomplish the tasks and reducing the efficiency of activity. This paper mainly report the study on relationship between different upper limb workloads and metabolic rate when subjects were dressing, undressed or with pressures. Specially, we focus on the relationship between heart rate and metabolic rate in clothes. The main conclusions of this paper is: Wearing different garments the correspondence between heart rate and metabolic rate are far from the same. And Liquid Cooling Garment (LCG) is the most effective garment for human metabolism among the clothes in this research. The pressures inside clothes increased workload, as well as the metabolic rate.