This page contains a Flash digital edition of a book.
RESEARCH ROUND-UP Exercise lowers prostate cancer deaths I


n a joint study from Harvard Medical School and the University of California, US, researchers tracked 51,529 male health professionals over an 18-year period. Among the 2,705 who were diagnosed with prostate


cancer, the amount and intensity of exercise undertaken was correlated with risk of death. Any form of activity conveyed a protective effect, but


the most signifi cant reductions in risk were associated with vigorous exercise. Compared to those who did the least amount of activity, those doing 10 or more hours of non- vigorous activity a week had a 49 per cent reduction in risk of death from all causes. Those doing more than three hours of vigorous activity a week had a 61 per cent reduction in risk of mortality


from prostate cancer – even though they had already been diagnosed with this condition. Researchers proposed a number of different mechanisms by


which exercise conveys its protective effects. Previous research has demonstrated that higher levels of insulin production and infl ammation are associated with increased risk of prostate cancer death. Exercise has been shown to increase the body’s sensitivity to insulin, resulting in lower insulin production, and reducing the levels of infl ammation. Physical activity has also been shown to boost the activity of the innate immune system – the body’s fi rst line of defence against infection or disease. While the present study was unable to identify which of


these mechanisms was responsible, it was considered likely that one or more contributes to the protective effects of exercise.


Kenfi eld, S.A. et al. (2011). Physical activity and survival after prostate cancer diagnosis in the health professionals follow-up study. Journal of Clinical Oncology. 29(6): 726-732


A fitter outlook – exercise improves vision


A


ccording to a review of the current research, exercise is associated with an improvement in two measures of visual prowess: contrast sensitivity and visual acuity.


Contrast sensitivity is the ability to distinguish between


overlapping, stationary and poorly outlined objects. For example, those with low contrast sensitivity may not be able to detect black letters on a poorly-lit white page, while those with high contrast sensitivity may be able to distinguish between two overlapping, near-identical objects from a distance in poor light. Visual acuity, meanwhile, is the ability to see fi ne detail. Athletes display higher levels of contrast sensitivity,


and while exercise may or may not directly improve this measure of vision, previous research has suggested that the chemical dopamine may play a part. Dopamine levels increase with exercise, and higher levels of this chemical have been shown to increase contrast sensitivity. In addition, the review showed that those who exercised


had better visual acuity than non-exercisers. Indeed, visual acuity was shown to improve during exercise – as the intensity of the participants’ cycling increased, so visual acuity improved. Researchers repeated the eyesight tests two days later and found that visual acuity remained higher than before exercise, indicating that you may be able to retain these gains in the longer term, not just during exercise. These improvements in visual acuity are thought to


result from the temporary boost to various systems and functions in the body that occur as a response to physical exertion: the body interprets exercise as a form of stress and instigates the primitive ‘fi ght or fl ight’ response. As part of this process, pupil size increases, allowing more light into the eye and enhancing visual acuity.


Zimmerman, A.B., Lust, K.L., Bullimore, M.A. (2011). Visual Acuity and Contrast Sensitivity Testing for Sports Vision. Eye & Contact Lens. 37(3):153-159


Walking women less likely to suffer stroke Study: Walking appeared more beneficial than cycling


study, researchers surveyed nearly 33,000 men and women and divided them by gender, the type of exercise undertaken and their total weekly exercise time. Interestingly, women who walked for 210 minutes or more


W


each week had a lower risk of stroke than those who cycled or did other higher-intensity workouts for a shorter amount of time. Another notable fi nding was that no reduction was seen for men based on type and frequency of exercise. The researchers did point out that their fi ndings might not


translate directly to the general population due to certain characteristics: the majority of subjects in the study were blood donors, who tend to be in good health in order to give blood. These characteristics make the group studied very specifi c, with notable differences versus the general population. That said, there is evidence to show exercise is related to a


reduced risk of stroke and other diseases, and that 30 minutes of moderate physical activity a day can help prevent disease.


Huerta, J.M. et al. (2013). Physical activity and risk of cerebrovascular disease in the European Prospective Investigation into Cancer and Nutrition-Spain study. Stroke. 44(1):111-8


44 Read Health Club Management online at healthclubmanagement.co.uk/digital April 2013 © Cybertrek 2013


omen who walk at least three hours a week are 43 per cent less likely to suffer a stroke than women who walk less or not at all, according to new research from Spain. In the


© SHUTTERSTOCK.COM


MEDICAL WELLNESS


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92