The BUAV is shocked by reports from the USA of researchers who subjected a group of long-tailed macaques to forced treadmill exercise before killing them. Their conclusion was that exercise benefits not only the body, but also the brain (1). The macaques, who were caught in the wild and imported to American laboratories a number of years ago, were forced to run on treadmills at speed for one hour a day, five days a week, for five months. Their cognitive skills were assessed periodically, and it was discovered that monkeys who had exercised more learned faster than more sedentary individuals. The animals were made to run on the treadmills at speeds with which they could not keep pace. At the end of the experiment, the monkeys were then killed and their brains removed for examination. The scientists concluded that the exercise regimen had increased blood flow to the brain (2).

Yet, substantial human data, including advanced techniques such as high-resolution MRI scans, have demonstrated the mental as well as physical benefits of exercise over many years, including evidence that exercise mitigates brain volume decline associated with ageing (3-9). The monkey experiments are simply proving in monkeys what we already knew in people. The authors of the report assert the importance of their research because they examined the brains of the monkeys for clues regarding the mechanism of improved cognitive function, something they claim is impossible for human subjects. This is not true, however, because careful physiologic studies on people, including imaging techniques such as MRI and CT scans of human volunteers, along with examination of tissues after death can reveal precisely what is relevant for human beings.

Using these highly intelligent monkeys for such frivolous experiments when we already have the information in people is just one more example to prove that researchers are misleading the public when they say animals are only used when it is necessary and then only for human life-saving research.

28th April 2010

1. ‘Exercise is good for the brain’, Livescience.com. 26th April 2010. Available at: http://www.livescience.com/health/exercise-improves-brain-100426.html

2. Rhyu IJ, et al., Effects of aerobic exercise training on cognitive function and cortical vascularity in monkeys, Neuroscience (2010), doi: 10.1016/j.neuroscience.2010.03.003

3. Etnier JL, Berry M (2001) Fluid intelligence in an older COPD sample after short- and long-term exercise. Med Sci Sports Exerc 33: 1620 –1628.

4. Khatri P, Blumenthal JA, Babyak MA, Craighead WE, Herman S, Baldewicz T, Madden DJ, Doraiswamy M, Waugh R, Krishnan KR (2001) Effects of exercise training on cognitive functioning among depressed older men and women. J Aging Phys Activ 9:43–57.

5. Colcombe SJ, Erickson KI, Raz N, Webb AG, Cohen NJ, McAuley E, Kramer AF (2003) Aerobic fitness reduces brain tissue loss in aging humans. J Gerontol A Biol Sci Med Sci 58:176–180.v.

6. Colcombe SJ, Erickson SI, Scalf PE, Kim JS, Prakash R, McAuley E, Elavsky S, Marquez DX, Hu L, Kramer AF (2006) Aerobic exercise training increases brain volume in aging humans. J Gerontol A Biol Sci Med Sci 61:1166–1170.

7. Colcombe S, Kramer AF (2003) Fitness effects on the cognitive func- tion of older adults: a meta-analytic study. Psychol Sci 14:125–130.

8. Gordon BA, Rykhlevskaia EI, Brumback CR, Lee Y, Elavsky S, Konopack JF, McAuley E, Kramer AF, Colcombe S, Gratton G, Fabiani M (2008) Neuroanatomical correlates of aging, cardiopul- monary fitness level, and education. Psychophysiology 45:825– 838.

9. Colcombe SJ, Kramer AF, Erickson KI, Scalf P, McAuley E, Cohen NJ, Webb A, Jerome GJ, Marquez DX, Elavsky S (2004) Cardiovascu- lar fitness, cortical plasticity, and aging. Proc Natl Acad Sci U S A 101:3316 –3321.