GOOD PRACTICE the Green Gym session.

It should be noted that not all individuals sustain such a consistently high level of activity for such long periods of time. Furthermore, this particular heart rate recording was made during a task that was taking place on a slope, thus adding to the intensity of the workload.

But this data

Figure 1: Comparison of heart rate response during two sessions of physical activity in a 40 year old woman

for periods of between 20 and 45 minutes. This level of intensity and duration would, if performed regularly, be sufficient to elic- it a ‘training effect’. In particular, activities using large muscle groups in a rhythmic manner such as raking, appear to elevate the heart rate to an appropriate level for sustained periods of time.

Detailed heart rate analysis of one participant To assess the potential benefit of taking part in a Green Gym session, heart rate data was collected from a 40 year old female who takes part in regular Green Gym sessions and also performs a step-aerobics class once a week. trated in Figure 1.

Estimates for Green Gym work rates are based on a sample one hour period taken during a morning-long session.

The con-

servation task in question consisted of sawing and felling young trees on a hillside and piling onto a bonfire.

The heart rate data (table 1)collected from this individual clearly illustrates that her estimated energy expenditure during a Green Gym session was significantly higher than during a step aerobics class. Furthermore, the average time spent in her ‘training zone’ - the level that would con- vey cardiovascular benefits - was longer for

In addition to limiting the amount of time spent on repetitive tasks, the report high- lights the need for hypertensives to avoid straining-type tasks such as lifting exces- sively heavy loads, pulling up brambles or pulling wire fencing tight. This type of activity can lead to a rapid increase in blood pressure that, for some individuals, may be dangerous. Participants in the Green Gym all complete a PAR-Q form on joining the project and are asked to con- sult their GP if they respond positively to

Table 1: Comparison of two sessions of physical activity (60 mins) Green Gym

Average time spent in ‘training zone’ Percentage of estimated maximum

heart rate in training zone Average bpm for 60 minute

sample period Estimated energy expenditure

44 minutes 70-85%

128 bpm 392 kcal

Step aerobics 24 minutes

70-80% 110 bpm 306 kcal

If you are involved in a different or unusual health promotion project and would like to be featured in future issues of SportEX Medicine send your project information to the SportEX office (address on page 4).

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does illustrate the ‘potential’ intensity of Green Gym sessions, should participants wish to work hard.

The results are illus-

A safe form of exercise Injury report forms are completed at each session and no significant injuries occurred during the period of the evaluation. Follow-up calls to non-adherers did not identify injury or discomfort as being a reason for attrition. This is likely to be attributable to the vigilance of the project leader in ensuring that participants ‘warmed up’ and ‘cooled down’ with a series of stretches and were reminded frequently of safe techniques when lifting, carrying and performing strenuous tasks. Emphasis is placed on encouraging participants to only undertake tasks that they feel are within their capabilities. Furthermore, par- ticipants are carefully monitored and encouraged to vary the tasks they perform and not engage in any one task for more than twenty minutes at a time.

any of the questions.

Interestingly, 82% of the Green Gym par- ticipants had never before taken part in conservation work. Most of them joined with the idea of getting fitter, but have stayed because they thoroughly enjoy being out in the countryside, doing some- thing worthwhile and meeting new friends.

OCHRAD are now carrying out a further research project evaluating the psycho- social benefits of the latest Green Gym pro- ject in Portslade, near Hove.

It is hoped

that this new venture will attract more than 100 volunteers.

Veronica Reynolds has a degree in exer- cise, health and psychology and is a researcher in health-related exercise at Oxford Brookes University. She was an advisor to BTCV for the exercise compo- nent of the Green Gym. At the time of going to press the Green Gym was due to be featured on BBC’s Breakfast TV.

References 1. Reynolds, V. The Green Gym - An evaluation of a pilot project in Sonning Common, Oxfordshire, 1999, Report No. 8, OCHRAD Oxford Brookes University 2. Kellert, SR and Wilson EO. The Biophilia Hypothesis. 1993 Island Press, Washington, DC, USA 3. Rantanen et al. Midlife grip strength as a pre- dictor of old age disability. 1999;281:558-560

JAMA

Resources ● The BTCV have produced A ‘Practical

Guide to Setting Up a Green Gym’. For more information telephone the BTCV on 01491 839766 ● To find out more about the Green Gym project contact Veronica Reynolds at OCHRAD on 01865 485293 ● The Countryside Agency have pro- duced a free and very comprehensive pack entitled ‘Practical Guidelines for Developing Walking Schemes’ (fea- tured in Issue 1 of SportEX Medicine). Telephone Peter Ashcroft on 01242 521381