Blog worthy New Heart Posts!

Tai chi improves postural stability in Parkinson’s disease

Individuals with Parkinson’s disease suffer from movement impairments that negatively impact balance which, in turn, adversely affects functional ability, quality of life and fall risk. Exercise is an important element of disease management in individuals with Parkinson’s. Resistance training has been show to be beneficial, but individuals require equipment and safety monitoring to do such training. Tai chi is a type of exercise focused on balance and is known to be beneficial in enhancing strength, balance, physical function, and fall risk in older adults. The current randomized, controlled study was conducted to determine the possible benefits of tai chi in individuals with Parkinson’s disease.

Subjects participated in a 24-week program of twice weekly exercise consisting of resistance training, stretching, or tai chi. Those in the tai chi group showed significant improvements in postural stability compared with those in the resistance training and stretching groups. Compared with the stretching group, the tai chi group also performed better in a number of secondary outcomes, including gait, strength, functional reach, timed up-and-go tests, and falls. The tai chi group also performed better than the resistance training group in gait and functional reach tests and had marginally fewer falls.

These findings suggest that tai chi may be an effective intervention that can improve postural stability, functional outcomes, and fall risk in individuals with Parkinson’s disease.

Fuzhong, L., et al. Tai chi and postural stability in patients with Parkinson’s disease. The New England Journal of Medicine. 2012;366:511-9.

Cardiorespiratory Fitness, Metabolic Risk Factors, and Mortality

Research has shown that mortality is particularly high among those with the lowest levels of cardiorespiratory fitness (CRF). The increased mortality in this group is primarily thought to be due to cardiovascular disease and cancer. While a sedentary lifestyle is partly responsible for this excess risk, there is also a clustering of cardiovascular risk factors found in individuals with low CRF. The current study looked at these risk factors to assess potential mechanisms that explain their effect. An analysis of 82,000 subjects showed that triglyceride and non-HDL cholesterol levels, systolic blood pressure, diabetes, and metabolic syndrome were all increased as CRF decreased. These risk factors are mostly metabolic in nature. While regular exercise can increase CRF and improve metabolic risk factors, it is insufficient to explain the strong correlation between these metabolic risk factors and CRF. Increased body weight is also associated with low CRF. This is significant because obesity, particularly upper body obesity, has a negative impact on metabolic risk factors. It is also possible that insulin resistance may impair muscular function or cardiorespiratory capacity. Future research will be needed to determine the exact mechanism by which cardiovascular risk factors increase mortality among individuals with low CRF.

Grundy, S.M., et al. Cardiorespiratory fitness and metabolic risk. American Journal of Cardiology. 2012;109:988-993.

Sitting Time and Mortality

A recent Australian study has shown that the amount of time we spend sitting can impact our health, regardless of whether or not we exercise. In a study of 222,497 individuals aged 45 or over, van der Ploeg and colleagues found that individuals who spend 11 or more hours per day sitting have a 40% increase in all-cause mortality compared with individuals who spend less than four hours per day sitting. This increase in mortality was similar in individuals who got no physical activity and those who exercise 150 or more minutes per week. It appears that, in order to maximize wellness, we need to spend less time sitting in addition to getting regular aerobic physical activity.

van der Ploeg, H.P., et al. Sitting time and all-cause mortality risk in 222,497 Australian adults. Archives of Internal Medicine. 2012;172(6):494-500.