Principles of Exercise Prescription Dr Victor Tan MBBS
Principles of Exercise Prescription • • • Dr Victor Tan MBBS, MRCP(UK), MMed(Int Med) Registrar Department of Sports & Exercise Medicine Changi General Hospital 1
Objectives • To understand the importance of exercise prescription • To understand components of an exercise program and prescription • To understand the importance of exercise progression • To be able to write an exercise prescription 2
EXERCISE IS MEDICINE SINGAPORE (Sample Exercise Prescription) Patient Name : John Doe Age: 57 Address : 2 Simei Street 3 Singapore 529889 RX: Moderately intense physical activity 30 minutes daily at least 5 times per week Or vigorous activity 20 minutes – three times per week of combination Resistance training twice a week Dr. Victor Tan Physician Signature : 3
Why is there a need for exercise prescription? • Scientific evidence shows that there are serious side effects and risk associated with inactivity. Exercise is indeed medicine and should be prescribed to every patient as needed • Clinicians can legally write and provide exercise prescriptions for patients • For clinicians, prescription pad is a familiar and comfortable way of transmitting advice and recommendations 4
Components of the Exercise Prescription Medication Prescription Exercise : Walk 30 minutes per day Strength : Moderate intensity Frequency: 5 times/week Precaution: Increase duration of walking slowly to avoid injury Medicine: Ibuprofen Strength : 600 mg tablets Route : Oral Dispense : 90 tablets Frequency: 3 times / day Precautions: Discontinue for stomach upsets 5
Essential Components of Exercise Prescription: FITT- VPro • Exercise Frequency (how often) • Exercise Intensity (how hard) • Exercise Type (type of activity) • Exercise Time or Duration (how long) • Exercise Volume (total amount) • Exercise Progression (how to advance) 6
Components of Exercise Training Session • Warm up: at least 5 -10 min of light to moderate intensity cardiorespiratory and muscular endurance activities • Conditioning: at least 20 -60 min of aerobic, resistance, neuromotor and/or sports activities ( exercise bouts of 10 min) • Cool down: at least 5 -10 min of light to moderate intensity cardiorespiratory and muscular endurance activities • Stretching: at least 10 min of stretching exercises performed after the warm up or cool down phase 7
Exercise Frequency For moderate intensity, frequency is about 3 to 5 days/week Deconditioned patients – lower intensity, shorter duration at higher frequencies For lower intensity, more than 3 days/week is required 8
Exercise Intensity Subjective Measure • • Relative difficulty of the exercise ( i. e. how hard the exertion feels) Different ways to measure exercise intensity Relative Measure Absolute Measure 9
Overview of PA Intensity Categories Measuring Exercise Intensity Subjective Measures “Talk Test” Perceived Exertion Relative Measures Absolute Measure Maximal HR (%) METs (10 point scale) Light Able to talk and/or sing <3 <64 <3 Moderate Able to talk, but not sing 3 -4 64 -75 3 -6 Vigorous Difficulty talking ≥ 5 >75 >6 10
Subjective Measure : The Talk Test • Low intensity – talk and sing • Moderate intensity – able to talk but not sing • Vigorous intensity – neither singing nor prolonged talking is possible 11
12
13
Relative Measures of Intensity • Percentage of maximal oxygen consumption (VO 2 max) • Percentage of maximum heart rate • Percentage of heart rate reserve • Simple method using percentage of maximum heart rate • Example : exercising at moderate intensity would be quantified as 64 % – 75 % of heart rate max. • Heart rate max is determined by the formula 220 minus patient’s age • For more accurate estimate can use HR max = 206. 9 – (0. 67 x age) 14
Intensity using Maximal Heart Rate (HR max) • Data : 51 -year-old patient to exercise at moderate intensity • Moderate- intensity exercise = 64% -76 %of HR max • Using HR max = 220 – 51 (age) =169 • Target Lower range = 0. 64 x 169 = 108 • Target Upper range = 0. 76 x 169 = 128 • Heart rate range 108 -128 bpm 15
Intensity using Heart Rate Reserve (HRR) % HRR Level of Effort Perceived Exertion <40% Light Intensity Easy to Comfortable 40 -59% Moderate Intensity Uncomfortable to Hard ≥ 60 % Vigorous Intensity Hard to Very Hard Target HR (THR) = { (HR max – HR rest) x % intensity desired } + HR rest 16
Calculating targeted heart rate using HRR Target HR (THR) = { (HR max – HR rest) x % intensity desired } + HR rest Example • Moderate intensity activity for a 51 year old individual with HR rest 76 bpm o. HR max (220 – age) 220 – 51 = 169 bpm o. HR rest 76 bpm o. Lower limit = 40% { (169 -76) * 0. 40 } + 76 = 113 bpm o. Upper limit = 59% { (169 -76) * 0. 59 } + 76 = 132 bpm *bpm = beats per minute 17
Absolute Measure of Intensity • Metabolic equivalents (METS) • One metabolic equivalent is the measure of the amount of oxygen/energy used by body when at rest ( resting metabolic rate ) • 1 MET = 3. 5 m. L /kg/min O 2 consumption • Useful way to describe the intensity of a variety of physical activities and work in relation to the individual’s ability. 18
Light < 3 METs Moderate 3 -6 METs Vigorous > 6 METs Walking slowly around home, store or office Brisk walking Hiking at steep grades Jogging Fast paced walking Household & occupation Sitting— using computer; work at desk using light hand tools Household & occupation Billiards Badminton– recreational doubles Basketball game Fishing– sitting Bicycling– on flat: light effort Fast Bicycling Playing most musical instruments Dancing– ballroom Soccer Golf Tennis singles Cleaning– heavy: washing windows, Shovelling sand, coal, etc. car Carrying heavy loads such as bricks Standing— performing light work Sweeping floors or carpet, such as making bed, washing dishes, vacuuming, mopping ironing, preparing food Leisure time & sports Swimming recreational / breast stroke Tennis doubles 19
Exercise Duration • Cumulative physical activity 30 -60 minutes/ day • Continuous or intermittent (at least 10 min each bout) 20
Exercise TYPE • Any form of physical activity which uses continuous and rhythmic movements of large muscle groups. • Examples: walking, jogging, running, biking, dancing, rowing, skating 21
Exercise Prescription Aerobic Activities Select modality based on co-morbidity and preference Wt bearing impact Running Step aerobics Skipping Stair climbing Jumping jacks Wt bearing Non/Low-impact Stair-master Elliptical trainer Low-impact aerobics (Dance) Non-wt b’ring Non-impact Cycling Rowing Swimming Water-based training Arm-cranking safety calories burnt 22
Exercise Volume • Volume ( Quantity) • Product of Frequency, Intensity and Time (FIT) • MET-min/week and kcal/week • E. g Jogging (at ~7 METs) for 30 min on 3 d · wk− 1 for a 70 -kg male: 7 METs × 30 min × 3 times per week = 630 MET-min · wk− 1 • Target volume of >500 -1000 MET-min/week which is approx 1000 kcal per week 23
Resistance Training Frequency • Involve all major muscle groups on 2 or more days a week non consecutive days • The 8 major muscle groups include: 1. Shoulders (deltoids) 2. Arms (biceps, triceps) 3. Chest (pectoralis major/minor) 4. Abdominals (rectus abdominalis, obliques) 5. Back (latissimus dorsi, rhomboids, erector spinae) 6. Glutes (gluteus maximus/minimus) 7. Thighs (quadriceps femoris, hamstrings) 8. Calves (gastrocnemius, soleus) 24
Resistance Training • Intensity • Muscle Endurance • Most adults: <50% 1 RM • Older adults and deconditioned: 20%-50% 1 RM • Time • Aim to complete 30 - 60 minutes per session • Type • Involving major muscle groups • Multi joint exercises 25
Resistance Training • Repetitions • 8 -12 repetitions for Muscle Strength • 15 -25 repetitions for Muscle Endurance • Sets • 2 -4 sets for strength and power • <2 sets for muscle endurance • Pattern • Rest intervals of 2 -3 minutes between each set of repetitions • Rest of >48 hours between sessions • Progression • Gradual progression of greater resistances and/or more repetitions per set, and/or increasing frequency 26
Resistance Training • Technique Recommendations • Move through full ROM of joint • Proper breathing techniques • Avoid Valsalva Maneuver • To avoid injury and muscle soreness , start at a lower intensity (RPE of 5 -6) or 15 repetitions to fatigue • It may be advisable to recommend the assistance of a qualified health and fitness professional at a local fitness club to familiarize with equipment and technique 27
Resistance Training Progression 28
Warm-up Involves low intensity activity specific to the exercise performed Prepares body for more strenuous exercise Improve blood circulation Increase the heart rate Reduce risk of musculoskeletal injury 29
Cool-down • Gradual recovery from the endurance phase: • Adjust the circulatory response (e. g. HR and BP) • Improve venous return • Reduce risk of post-exercise hypotension and dizziness 30
Flexibility Exercise • Improve ROM • Most effective when muscles are warm • Variety of static, dynamic and proprioceptive neuromuscular facilitation (PNF) exercises 31
Flexibility Exercise • Frequency • >2 -3 days per week • Intensity • To the point of tightness or slight discomfort • Time • Hold static stretch for 10 -30 s • For PNF stretching, 3 -6 s light to moderate contraction followed by 10 -30 s assisted stretch 32
Flexibility Exercise • Type • Major muscle tendon units • Static, passive, dynamic, ballistic, PNF are effective • Volume • 60 seconds of total stretching time 33
Establish physical and motivational readiness Is it safe to start ? Pre contemplation or Contemplation ? Type and Intensity Use a 10 point confidence scale, ask patient the duration he can commit per day E. g. walking Start at low to moderate intensity Frequency Start at 3 per week 34
Case Study • Mr. James T • 54 year old sedentary man • Moderate risk • It is safe for him to exercise at low to moderate levels • Worried of his steady weight gain and has decided on walking 35
James, I am glad that you are ready to begin making yourself healthy through physical exercise. I think a good way for you to get started is to commit to walking around your block for at least 20 minutes a day 3 times a week. The eventual goal will be to work up to 30 minutes of moderate intensity walking 5 times a week. But remember, we are going to start with the regular and worry about the exercise part latter. Can you commit to walking at least 20 minutes per day at least 3 days per week for a start ? Begin with F =3 per week I = moderate ( can sing but cant talk) T= 20 minutes a day T= Walking Total = 3 x 20 = 60 minutes/ week Goal is to achieve 30 x 5 = 150 minutes of moderate activity per week i. e. National recommendations Prescription in less than 30 seconds 36
• Well , maybe but I am really busy at work 37
Ok. How about starting out at 15 minutes each time but on a regular schedule ? Use a 10 point confidence scale, ask patient the duration he can commit per day On a scale of 1 to 10, how confident are you that you can do this 3 times a week ? James: That seems more realistic. I will walk Sat, Sun and Wed I am 7 out 10 confident that I can do this 38
• Great James. Let’s start there. • To begin with, walk at a pace that is comfortable for you. Over time, you will be walking at a brisker pace. • Keep a log of the current level for 2 weeks. If that works out for you, try going for about 20 minutes 3 x per week. Before sending your patient off to start , consider how you would want to progress the exercise program to meet the recommended 150 minutes / week • I look forward to seeing you log on your next visit in 3 weeks 39
Summary of Principles of Exercise Rx FITT-VPro • Set SMART goals • Frequency • Intensity • Time / duration • Type of activity • Volume • Progression • Focus first on regular in regular exercise • Gradual change leads to permanent change • More exercise is better than less but something is better than nothing 40
Thank You! 41
- Slides: 41