Results from M-CHAT study: liver fat associations with physical activity
August 19, 2014
A study recently published by CoHeaRT’s Iris Lesser, Danijela Gasevic, Scott Lear, and others, looked at whether physical activity could predict future liver fat accumulation. Those who are obese or have diabetes, high cholesterol or high triglyceride levels are more at risk of developing excess liver fat. Liver fat is also a risk factor for heart disease.
The authors compared physical activity levels of participants at the beginning of the study and liver fat accumulation at 5-year follow-up. They wanted to see whether the amount and intensity of physical activity in the year prior to the beginning of the study had an influence on liver fat at five year follow-up. Looking at moderate, moderate-vigorous and vigorous physical activity, the authors found that only vigorous physical activity was associated with lowered liver fat accumulation.
Physical activity rates are measured in metabolic equivalents (METs), where 1 MET is equal to metabolic rate at rest. Moderate activity is defined as 3 – 5.9 METs; in practical terms, these are activities such as brisk walking, which generate some sweat and harder breathing. On the other hand, high-intensity activities such as jogging are defined as 6 METs or more.
Current Canadian physical activity guidelines for adults aged 18 – 64 suggest 150 minutes of moderate to vigorous physical activity per week, in at least 10 minute intervals. Although moderate physical activity has many benefits, this study did not find that moderate activity alone was enough to alter liver fat.
These findings are part of M-CHAT, the Multicultural Community Health Assessment Trial, which examined how body fat distribution differs among ethnicities. Aboriginal, Caucasian, Chinese and South Asian groups were compared.