Scaling Perceived Exertion

Psychophysiolgoy Relationship between physical stimuli & perceptual responses Relationship between body & mind

Exertional Mediators: Physiological Respiratory / metabolic Ventilatory Peripheral Acidosis Non specific Hormones

Exertional Mediators: Psychological Emotion & mood Cognitive function Perceptual processes Social or situational

Modern Approaches Direct assessment Scale sensations Study sensory response Scale sensations Magnitude estimates of perceived exertion Interindividual comparisons not possible Catergory scaling Interindividual comparisons

Borg (1961) 21-pt 1 2 3 Extremely light 4 5 Very light 6 7 Light 8 1 2 3 Extremely light 4 5 Very light 6 7 Light 8 9 Rather light 10 11 Neither light or laborious 12 13 Rather laborious 14 15 Laborious 16 17 Very laborious 18 19 Extremely laborious 20

21 – pt Studies Borg 1961: n = 12 Cycling at 100, 300, 900, 1200kpm/min RPE not linear with HR or Power Borg, Dahlstrom 1962: n = 28 (14 & 15) Linear relationship with HR, PO Borg, Linderholm 1967: n = 61 males (18 to 79) HR declined with age at all Powers, RPE equal or increased with age

Borg (1971) – 15 pt 6 7 Very, very light 8 9 Very light 10 11 Fairly light 12 13 Somewhat hard 14 15 Hard 16 17 Very hard 18 19 Very, very hard 20

Borg (1985) – 15 pt 6 No exertion at all 7 Extremely light 8 9 Very light 10 11 Light 12 13 Somewhat hard 14 15 Hard (heavy) 16 17 Very hard 18 19 Very, very hard 20 Maximal exertion

15 – pt Studies Borg (1971): Linear relationship between HR, Power and RPE Noble et al. (1986): RPE is dependent on mode of exercise

Borg (1983) 10 - pt 0 Nothing at all 0.3 0.5 Extremely weak (just noticeable) Very weak 1.5 Weak (light) 2.5 3 Moderate 4 5 Strong (heavy) 6 7 Very strong 8 9 Extremely strong Maximal

10 – pt Studies Noble et al. 1983 Blood lactate and RPE increase similarly with quadratic trend Muscle lactate increased with a cubic trend HR increased linearly

Omni Scale Artist drew pictures: represent physical exertional state. Stimulus given to subjects verbal description of made 6 verbal cues collected for adults (easy and hard) and 6 for children (tired). Pictures & cues placed at equal intervals in 0 to 10.

Omni Adult Walking

Omni Adult Cycling

Uses of RPE

Perceptually Regulated Exercise Prescription To define the cardio respiratory training zone Regulate training intensity Estimation – production paradigm Production only paradigm

Perceptual Estimation-Production Prescription RPE linked to clinical events during GXT Two stage process: ID target RPE estimated during a GXT RPE is then produced during exercise

RPE Estimation RPE taken at GXT stages Max VO2 identified E.g 70 & 85% max identified Training RPE identified

RPE Production Client titrates exercise intensity Related to high/low intensities on GXT Overload is ‘natural’

Perceptual Production-Only Prescription Recommended for normal subjects only Identify ‘known’ intenstiy for benefit CV training Weight loss Good evidence base for AnT 12 – 14 50 – 80%max

Examples of Other Scales Clinical Subscales

The Angina Scale 1+ Light, barely noticeable 2+ Moderate, bothersome 3+ Severe, very uncomfortable 4+ Most severe pain ever experienced in the past

Gagge, Stolwijk, Hardy ACSM (1986) Comfortable sensation (1967) 2 Slightly uncomfortable 3 Uncomfortable 4 Very uncomfortable

Clinical Guidelines & applications

Classification of PA intensity Pollock et al. 1990 / ACSM 1995 Relative Intensity Intensity   %VO2max %HRmax RPE Very light <30 <35 <10 Light 30-49 35-59 10 to 11 Moderate 50-74 60-79 12 to 13 Heavy 75-84 80-89 14 to 16 Very heavy >85 >90 >16

RPE for Rehabilitation Borg 1998 Exercise should be started at 9 to 11 After a while progress to 13 When exercise is hard :15 it is too hard!!!

RPE for Cardiac patients Phase IV (BACR 2006) Use of RPE during GXT Use of RPE during the exercise sessions Use of RPE at home-based activity in a recorded log: frequency, duration, intensity, self monitoring of pulse rate Warm-up at RPE 10 to 11 (that is “light”) Main exercise program at RPE 12 to 15 (that is “somewhat hard” to “hard”) In neuropathy use of RPE is recommended

RPE for Cardiac patients Phase IV (BACR 2006) It is important not to rely on any single indicator of exertion levels, such as RPE or pulse rate. Participants signs and symptoms responding appropriately to the activity: Excessive breathlessness Loss of quality of movement Skin colour sweat rate

Clinical applications of RPE (ACSM 1997) Disease 6-20 scale OMNI scale Myocardial infarction 11 to 16 4 to 7 CABG or PTCA 12 to 14 5 to 6 Valvular heart disease 11 to 14 Congestive heart failure Cardiac transplant Hypertension 11 to 13 4 to 5 Pulmonary disease

Task What is the problem with exercise intensity and b-blockade?