It seems as though the benefits of an active lifestyle have long been known (Voss, Nagamatsu, Liu-Ambrose, & Kramer, 2011):
“A strong body makes the mind strong.” – Thomas Jefferson
“If we could give every individual the right amount of nourishment and exercise, we would have found the safest way to health.” – Hippocrates
There is strong link between physical activity and physical health. In fact, getting out and moving has been shown to decrease the risk for cardiovascular disease, osteoporosis, diabetes as well as both colon and breast cancer (Kelley, 1998; Laaksonen et al., 2005; Lee, 2003; Shiroma, 2010). But many may not be aware of the impact exercise has on brain functioning (Hillman et. al., 2008; Voss et al., 2011), and more importantly, the type and duration of exercise needed to positively impact brain health.
Studies have shown that when school-age children engage in physical activity they demonstrate improved cognitive performance. These children showed improvement in IQ, perceptual skills and achievement. They also performed better on tests of verbal and mathematical skills. Those children who exercised regularly also demonstrated higher levels of development and increased academic readiness (Sibley & Etnier, 2003). This exercise-related improvement was not found in young adults (potentially due to the fact that cognitive health peaks during this period of development; Salthouse, 2006), which means that it is important for children to get regular exercise because they can not simply make up for what they have missed as they get older.
Research indicates that older adults who maintain a healthy diet and exercise plan as well as remain socially and intellectually engaged have better cognitive functioning than their peers who do not (Karp et al., 2006). In fact, for those who have been diagnosed with early Alzheimer’s disease, a combination of aerobic and strength training has shown to improve performance in a number of areas including speed of information processing, visual and spatial memory, planning and inhibition when compared to those who engage in only one type of exercise or the other. In this study short bouts of exercise of 30 minutes or less had very little impact on cognitive functioning in this population (Colcombe, S. & Kramer A.F., 2003).
In addition to improving how people think, exercise has also been shown to improve how people feel. Physical activity has been show to improve both anxiety and depression (Davis et al., 2010; Krogh, et al., 2011; Rimer, 2012; Cooney et al. 2013).
Once we understand the benefits of exercise, the next natural question then becomes how much do we need to do in order to get these benefits? The first key is to focus on the type of activity that you are doing. We now know that combining strength training with aerobic activity has the highest impact on brain function/health (Colcombe & Kramer, 2003; Colcombe, 2006). We also know that aerobic exercise (running, walking, swimming etc.) is better than simply stretching and toning when it comes to improving brain functioning (Colcombe, 2004). Resistance or strength-training alone (e.g., lifting weights) has only been shown to improve memory when the duration of the program is at least six months but does not seem to have a positive impact on any other areas of cognitive functioning (Tsutsumi et al., 1997; Kimura, 2010).
In order to maximize the benefits of any physical exercise program the duration should be at least six months or more and each session should be 31-45 minutes in length as shorter sessions have not been found to be as helpful for improving brain health (Colcombe & Kramer, 2003). Remember to check in with your doctor prior to starting any exercise program, especially if you have not exercised in a long time or have health concerns.
Take Home Message:
1) Type: combined strength training with aerobic activity
2) Session Duration: 31-45 minutes
3) Duration: 6 Months +
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