The methods to assess physical activity and energy expenditure

To correctly assess physical activity is the key to study the relationship between sports and health,between exercise and efficiency.In recent decade years,many researchers have tried to find an objective、accurate and reliable m ethod to assess physical activity.The activity data processing instrument based on accelerometer which appeared only a few years ago provides a new thinking m ethod and practical technique.This paper sum marized the recent developm ent in this field,and it also introduced the principle and specific m ethod when using the new type of instrument based on three- dim ensional accelerom eter to assess physical activity.