It is clear from the evidence that physical activity is good for physical and mental health, and for learning, but what is not clear is exactly how much is required and at what intensity to reap all these benefits.
The recommendation from various international and national bodies generally for physical health is at least 30 minutes of moderate physical activity most days of the week. Moderate activity is equivalent to brisk walking. The 30 minutes need not be in one unbroken stretch of activity. (1)
The recommendation above is also relevant to those who are over 55. Those who are frail and elderly may benefit more from strength and balance training rather than aerobic exercise.
Children and young people
The recommendation from most authorities is that they should participate in at least 60 minutes of moderate activity every day. Again this can be ‘accumulated’ throughout the day. On two of these days the exercise should be ‘vigorous’.
Dr John Ratey's recommendations for young people’s learning and mental well-being
Ratey and colleagues do not recommend a return to traditional types of physical education in schools but ‘aerobically demanding activity on a daily basis. This type of activity should focus on ‘personal progress and lifelong fitness activities by encouraging modes of physically strenuous play that are engaging, challenging and enjoyable to students.’ (2) This could include personal fitness programmes, traditional games, strenuous play and social dancing.
Dr Ratey’s recommendation in Spark
Dr Ratey recommends adults spend about 6 hours of exercise a week to get real brain benefits. This is more demanding than the general recommendation on health and physical activity. (30 minutes most days.) In Spark he specifically advocates:
- Some type of physical activity 6 days a week for 45-6- minutes. 4 of these should be 'moderate' (eg a brisk walk) and 2 should be shorter but higher intensity.
- On the high intensity days also do some form of strength or resistance training.
- Do not make the high intensity days back to back but space them out to ensure recovery time.
Ratey recognises this is demanding but points out that it sill constitutes only 5% of our waking hours. He wants people to realise that the most important thing is to do some type of physical activity even if it is not the ideal type or duration.
1. See, for example, Let's make Scotland More Active: A strategy for physical activity. The Physical Activity Task Force, Scottish Executive, 2003.
2. John J. Ratey and Eric Hagerman, Spark: The Revolutionary New Science of Exercise and the Brain, Little Brown, New York, 2008, page 370.