An hour of exercise a day may compensate for an 'office lifestyle'

Conclusion This study helps to disentangle the effects of having a sedentary lifestyle and being physically active. Previous studies have had conflicting results, with some saying that sitting for long periods can be counteracted by taking exercise, while others disagreed. The advantage of this study is that it looks at time spent sitting as well as time spent being physically active, and calculates how both are linked to mortality and to each other. The study has many strengths, not least its size. It includes data from 1,005,791 people from 16 studies. The researchers applied a standardised protocol and asked study authors to provide re-analysed data. This meant they could pool information and make direct comparisons between groups sub-divided by sitting time and activity levels, to a higher degree of accuracy than would otherwise have been possible. However, there are limitations. The authors only included English-language papers, so other relevant studies may have been excluded. The authors tried to account for what is called reverse causation – in this case that illness may have prevented people from being physically active – by including studies of apparently healthy adults. However they admit that this factor was not completely ruled out. In addition, the data came from participants' own estimates of time spent sitting, watching TV and being physically active. Not only is this reliant on accurate (and honest) self-assessment, it was only measured at one time po...
Source: NHS News Feed - Category: Consumer Health News Tags: Lifestyle/exercise Heart/lungs Source Type: news