A pilot study to inform future research into the use of ankle weights with adults who are learning disabled

The primary outcome measure will be percentage body fat (i.e. the percentage of total body weight that is fat). Body fatness is associated with morbidity and mortality. Percentage body fat will be measured using Tanita body fat scales; these scales use bioelectrical impedance and have been demonstrated to be accurate at measuring percentage body fat (Ohno, Nishisaka, & Ikeda, 1998; Utter, Nieman, Ward, & Butterworth, 1999).

Additional outcome measures are:
Body Mass Index (BMI): is a measure of the degree of overweight, in relation to an individual’s height (Height/weight2). BMI is a predictor of morbidity and mortality due to numerous chronic diseases and predicts more variance in health risk than does Waist Circumference alone (Janssen, Katzmarzyk, & Ross, 2004).

Waist circumference (WC): is a measure of abdominal obesity gained using a tape measure (Aronne & Segal, 2002). It relates closely to BMI yet is a simpler measure to obtain. It is the best indicator of changes in intra-abdominal fat during weight loss (Lean, Han, & Morrison, 1995). A higher WC measurement indicates higher health risk and the addition of waist circumference to BMI predicts a greater variance in health risk than does BMI alone (Janssen et al., 2004).

Cardiovascular function: Resting systolic and diastolic blood pressure and heart rate measurements will be taken at each time point using a sphignomanometer.

Rate of Perceived Exertion (RPE): Perceived Physical exertion is a measure of how hard someone feels they are working during exercise and should decrease as a person’s fitness level improves (Borg, 1998). RPE will be measured using the OMNI Picture System of Perceived Exertion (Robertson, 2004). The OMNI walking to running scale will be used: this has a set of picture and verbal cues in conjunction with a numerical rating scale of 0 to 10 (with 0 being 'not tired at all' and 10 being 'very, very tired'). Research studies have established the validity and reliability of the scales (Robertson, 2004).
Participants will indicate how they feel on the walking scale (a copy of the scale is provided in the protocol Appendix). The physiotherapy technicians will make a judgement about how tiring those participants who have difficulty using the rating scale felt during the walk via physical signs of exertion (i.e. breathing, sweating, ease of talking) - a key has been developed to ensure consistency in how physical signs of exertion are interpreted by physiotherapy technicians.

Talk test: As the OMNI picture system has not been validated with learning disabled adults and some adults may not be able to indicate how they feel on the scales, the physiotherapy technicians will carry out an objective talk test with participants during the walk. Someone who is active at a ‘light’ intensity level should be able to sing whilst carrying out an activity. Someone who is active at a ‘moderate’ intensity should be able to carry out a conversation comfortably while engaging in an activity. If a person is too tired or out of breath to carry on a conversation the activity is considered ‘vigorous’ (Centers for Disease Control and Prevention, 2005).

Number of steps taken during the walking group walk will be measured. Participants will wear pedometers Yamax Digi-walker SW-200 pedometers (consistently rated in the ‘top ten’ by independent research reviews (Cavill, 2005).