Exercise Prescription Aerobic Fitness

Principles of Training Overload – Harder work than the body is accustomed to.  Training Variables (FIT Principle)  F requency - number of times per week  I ntensity - level of the effort at any given time; speed, weight, hills, water resistance, etc.  T ime - duration, reps/sets in weight training  Frequency and duration together are often referred to as training volume. In weight training volume is often reps/sets (volume per exercise session).

Principles of Training Specificity - Adaptations that occur are specific to the type of training performed.

Principles of Training Progression  Gradually increase the overload in an exercise program over time.  Prevents possible injury and frustration.  NOTE: Increase training volume first, then intensity.

Principles of Training Progression – Sedentary but low risk  Table 7-1, Page 149 –Initial Stage – 4 wks. –Improvement Stage - ~ 20 wks. –Maintenance Stage – lifelong !

Principles of Training Reversibility –Training adaptations (improvements) will be lost if training is stopped for a prolonged period of time. –In general, the faster the adaptation occurred, the sooner it will be lost once training stops.

Aerobic Fitness Target Heart Rate, METs, and RPE 1.Target Heart Rate  Target HR range = 55/65 – 90% HRmax  Heart Rate Reserve (Karvonen) Method: oTarget HR range = 40/60 – 80% HRR THRR = [(HRmax – RHR) x.40/.50 to.85] + RHR

A erobic Fitness Target Heart Rate, METs, and RPE 2.Target VO 2  VO 2 Reserve = [( VO 2 max – VO 2 rest ) x % intensity] + VO 2 rest

A erobic Fitness Target Heart Rate, METs, and RPE 3. Metabolic Equivalents (METs):  One MET = 3.5 ml/kg/min (VO 2 )  Target METs = Target VO 2 (ml/kg/min)/3.5 ml/kg/min  Target VO 2 based on reserve (R) concept: VO 2 R = [(VO 2max – VO 2rest ) x % intensity] + VO 2rest  Note: current ACSM recommendations suggest using % of VO 2 R instead of % of VO 2max

Aerobic Fitness Target Heart Rate, METs, and RPE 4.RPE – Rating of Perceived Exertion  Category Scale (6-20) – Borg Scale  Category-Ratio Scale (0-10); Table 4-7, Page 77.

Aerobic Fitness Target Heart Rate, METs, and RPE General Points for THR, METs, and RPE:  These all represent exercise intensity.  THR and RPE are most commonly used.  METs (target VO 2 ) can be problematic because: METs cannot be easily monitored in many exercise settings. METs will vary with skill level and conditioning in various exercises (e.g., running vs. swimming).  THR can be problematic if it is based upon predicted HRmax (220 – age; error of ± 10 bts/min)

Aerobic Fitness Target Heart Rate, METs, and RPE Caloric Expenditure Guidelines  Another guide for exercise prescription  Expend 150 – 400 Kcal/day (150 for low fitness level)  Caloric cost of exercise:  Kcal/min = [METs x 3.5 x BW (kg)]/200  Note: Caloric expenditure takes into account all three components of overload (FIT).

Aerobic Fitness Exercise Duration and Frequency Duration  The duration is dependent upon the intensity.  To achieve health/fitness benefits, ACSM recommends 20 – 60 min of continuous or intermittent (10-min bouts) of exercise at 60 – 80% of HRR (VO 2 R).  Higher intensity can allow for less time.  Lower intensity should be accompanied by a longer duration.

Aerobic Fitness Exercise Duration and Frequency Frequency  ACSM recommends 3 – 5 days per week.  If intensity is low, greater than 3 days/week may be necessary to achieve weight loss goals.

Aerobic Fitness Metabolic Calculations Metabolic calculations are used to:  Determine predicted maximal exercise aerobic capacity (VO 2max )  Determine exercise intensities based on test data (THRR, %VO 2 R/METs, RPE)  Establish treadmill, cycle, and stepper settings to achieve target exercise intensities. Appendix D!!

Aerobic Fitness Metabolic Calculations Key Terms:  Gross VO 2 represents both the resting and exercise VO 2 components.  Net VO 2 represents only the exercise VO 2 component.  Absolute VO 2 represents the oxygen consumption for the total person (l/min).  Relative VO 2 represents the oxygen consumption per unit of body weight (ml/kg/min).

Maintenance of Training Effect Training adaptations are maintained if intensity is maintained, even if frequency and duration are reduced. This applies to both muscular adaptations and aerobic adaptations. Training improvements begin to decline relatively quickly with complete inactivity (as soon as two weeks). Principle of reversibility.

Special Populations 1.Cardiopulmonary Patients (Chapters 8)  Primary goal is to regain functional capacity (i.e. return to work status, ability to perform tasks of daily living).  Primary consideration is to establish exercise intensity below threshold for onset of problems.  Cardiac patients:  Pulmonary Patients:

Special Populations 2.The Obese (Chapter 9)  Primary goal is likely fat reduction while trying to maintain lean body mass.  Obese individuals will likely lose lean body mass along with fat mass, but the goal is to minimize this.  Focus will be on aerobic activity.  Generally recommended to reduce/expend 500 – 1,000 kcal/day to lose body fat. Acceptable loss is 1% of body weight/week (1.0 – 2.0 lbs/week for avg. person). oExercise objective is to expend >300 kcal/day. oShould not reduce total kcal/day intake below 1,200 kcal.

Special Populations 3.Diabetics (Chapter 9)  Goal is to follow general fitness guidelines and maintain blood glucose homeostasis.  Monitor blood glucose before, during, and after exercise if taking insulin or oral medication.  Avoid exercise at peak insulin times.  Do not exercise if blood glucose is > 300 mg/dl or >240 mg/dl with urinary ketone bodies.  Take CHO if blood glucose is < 80 mg/dl.  Note: Table 9-2 (page 209) provides summary of extreme glycemic signs and symptoms.

Special Populations 4.Hypertensives (Chapter 9)  General goal is to provide well-rounded fitness program that minimizes risks associated with hypertension.  Follow general recommendations for aerobic FIT, with slight reduction in intensity (40% - 70% VO 2 R).  Emphasis on aerobic activity.  Monitor blood pressure before, during, and after exercise.  Avoid high-intensity resistance training (lower intensity, higher repetitions).  Clients should maintain hypertensive medications, if prescribed.  Do not exercise if resting SBP > 200 mm Hg or DBP > 115 mm Hg.  Stage 3 hypertensives should begin pharmacological treatment prior to starting exercise program (controlled BP prior to starting).

Special Populations 5.Pregnant Women (Chapter 9)  Exercise is generally O.K. for pregnant women with no complications.  Intensity should be moderate (high intensity not recommended).  Factors to consider:  Avoid high-impact activities – vertical or horizontal!  Be cautious with activities requiring balance as center of gravity changes during pregnancy.  Avoid large increases in body temperature.  Proper hydration and increased caloric intake for exercise and fetal needs are important.

Special Populations 6.Children (Chapter 10)  Primary goal is to have participate in regular physical activity (not necessarily exercise).  Attention should be paid to avoid injuries due to improper exercise/activity.  Overuse injuries, often the most common form of injuries in children. oBe cautious of too much activity (volume) and high intensity.  Be cautious of exercise in heat and cold environments. Children do not respond to extremes as well as adults.

Special Populations 7. Elderly (Chapter 10)  Generally follow the same prescription guidelines for the regular adult population.  Consider mode – orthopedic and balance friendly  Consider accessibility  Consider group setting for adherence  Duration vs. intensity – frequent shorter bouts

Questions?

End Prescription Aerobic Fitness