Scientific Basis for Improving Muscular Strength and Endurance Flashcards
(44 cards)
1
Q
Introduction to Resistance Training
A
- PTs address issues of muscular performance: strength, endurance, power, resistance exercise
- strong theoretical background allows common language, practical application of muscle training
2
Q
Strength
A
- defined as max voluntar force produced by NM system: 1 RM
- increased strength occurs secondary to lifting heavy loads, for relatively low repetitions, involves complex set of interactions (neurological, muscular, biomechanical)
- numerous benefits associated with PRE
3
Q
Benefits of Resistance Training
A
- only PRE maintains muscle mass through adulthood
- untrained lose 5-7 lb of muscle every decade
- only PRE slows muscle loss associated with decreased RMR
- untrained show 2 to 5% decrease every decade
- increase 3 lb muscle mass which increases RMR by 7% and daily caloric requirements by 15%
- adults who strength train burn more calories all day long
- most adults do not use PRE yet can replace muscle mass lost through inactivity
- PRE found to increase total muscle area by 11.4% in previously untrained
- improves body composition by increasing fat-free weight
- appropriate use shown to increase bone mineral density and CT strength
- increases glucose uptake
- alters and enhances skeletal muscle carbohydrate metabolism, insulin action
- increases GI transit time 56% in 3 months, delayed GI transit time is linked to increased risk of colon cancer
- shown to decrease RBP
- improvements in blood lipid profiles similar to aerobic exercise
4
Q
Muscular Adaptation to PRE
A
-increased ability to generate force after RPE due to hypertrophy of muscle: increased cross-sectional area, increased synthesis of actin and myosin
5
Q
Isometric Resistance Exercise
A
- static muscle action: no change in joint angle
- studies typically show static strength gains…
- muscle at optimal length
- holding for 5-6 seconds
- 60-100% MVC (maximum voluntary contraction) show fastest gains
- 35-60% of MVC show slow increase
- 20-35% of MVC maintain strength
- less than 20% lose strength
- men increase 6%/week and women 4%/week
6
Q
Isometric Resistance Programs: Advantages
A
- requires little time
- no expensive equipment needed
- can be performed anywhere
- usually causes little soreness
- easy to maintain
7
Q
Isometric Resistance Programs: Disadvantages
A
- poor strength development through ROM
- no training of nervous system in a movement
- progress is difficult to assess without cable tensiometer (i.e. training is boring)
- can produce high SBP and DBP
- isotonic and isometric produce greater, more functional strength gains
8
Q
Isotonic Exercise Programs
A
- train muscles through available joint ROM
- external load remains constant
9
Q
Advantages of Isotonic Programs
A
- most common form of resistance training used by healthcare and exercise professionals
- builds strength throughout a ROM
- provides some training of nervous system
- progress is easy to follow as weight is added
- can be adapted to mimic functional motions
10
Q
Disadvantages of Isotonic Programs
A
- moderately expensive
- often results in soreness
- may expose novices to injury
- longer training sessions
- entire ROM not maximally trained secondary to sticking points (part where motion is most difficult)
11
Q
Isokinetic Exercise Programs
A
- train muscles through available joint ROM
- limb velocity remains constant
- velocity controlled by dynamometer
- limb velocity and force values recorded by microcomputer
12
Q
Advantages of Isokinetic Programs
A
- max resistance at all points in ROM
- can be performed at different speeds
- same device can test full spectrum of muscles
- provide a force readout for analysis
13
Q
Disadvantages of Isokinetic Programs
A
- very expensive
- can test only onemuscle
- often limited to open-kinetic chain motion
- affords little re-training of movement dysfunction
- non functional strength?
14
Q
Exercise Training Principles
A
- overload
- intensity and volume
- specificity
- cross training
- overtraining
- precautions
15
Q
Overload
A
- cells possess capacity to adapt to external stimula
- increased training load challenges an individuals current level of fitness
- initial response is fatigue and adaptation to training load
- overload causes fatigue, recovery, and adaptation
- overload is increase in training load leading to adaptation in muscle, etc
- its called PRE
16
Q
Overload for Increasing Muscular Strength
A
- tension is the stimulus
- inactivity –> lose 2-3% of strength/day
- recommended loads: 60-85% of 1RM
- attempt to increase loads or reps in every session
- best results occur with 8-12 reps
- if less than 12 increase weight
- low reps with high load
17
Q
Overload for Increasing Muscular Endurance
A
- high reps with low load
- recommended load: 15-40% of max
- work to fatigue
- tends to be boring
- need to watch for overexertion and substitution
18
Q
Intensity
A
- strength of stimulus, quality of effort, concentration of work per unit time
- ex of quantification of intensity…
- endurance or speed expressed as % VO2max
- maximum HR
- speed in m/s
- strength
- vertical jump
19
Q
Volume
A
- amount of training performed, sum of all repetitions or their duration
- ex of quantification of volume…
- kg lifted
- meters run
- number of throws or jumps taken
- number of sets and reps performed
- minutes or hours of training time
20
Q
Intensity and Volume
A
- use small loads (low intensity) with beginners or deconditioned, avoid too much overload, avoid possible injury
- take care in recommending too great an increase in either intensity or volume
21
Q
Specificity
A
- aka as specific adaptation to imposed demands (SAID) principle
- nature of training load determines training effect
- each type of training has its own specific training effect
- load must be specific to individual and activity for which they are training
- design program to meet demands or expectations
- consider energy demands, biomechanics of equipment, and functional carryover
22
Q
Overtraining
A
- progressive increase in training stimulus necessary to increase functional level
- yet individual may not take sufficient time to fully recuperate after chronic bouts of training
- occurs when body’s adaptive mechanisms repetitively fail to cope with chronic training stress
- may result in decreased performance, undue fatigue, possible substitution patterns, or injury
23
Q
Additional Principles of Training
A
- perform each rep thru full ROM
- speed of execution–>type of strength gain
- include eccentric contractions
- avoid jerky movements
- design workouts from larges to smallest
24
Q
Precautions
A
- client should not hold breath during exertion
- exhale during lift, inhale during recovery, breathe during exercise
- muscle soreness may develop secondary to exercise
- delayed onset muscle soreness develops 24-48 h after exercise, resolves within a week, linked to eccentric exercise
25
Periodization
- gradual cycling or phasing of specificity, intensity, and volume of training
- based on Seyle's GAS
- goal is optimal development of performance capacities
- helps prevent plateau in performance, overtraining, or injury
- consists of periodic changes of objectives, tasks, and content of training
- division of training year to meet specific objectives
- plan that changes workout sessions at regular time intervals
- training year typically comes to a definitive climax to a competitive season
- principles not limited to PRE
26
Periodization: Preparation Phase
- goal is major gain in strength to provide foundation for obtaining: power, muscular endurance, speed, and skill
- facilitates NM adaptation through high volume of activity
- training done ~3 times per week
- employs gradual shift in emphasis from volume to intensity and skill
27
Periodization: Competition Phase
- goal is to avoid de-training effects during competitive season
- PRE progresses to minimum maintenance phase while sport-specific skill training takes priorit
- PRE sessions decrease to 2 times per week, usually less than 20-30 minute
- total number of sets kept low: depends on goal of strength/power vs endurance; 1-4 sets; reps vary low to high-5-8 for strength/power, 10-25 for endurance
- longer rest periods between sets
28
Periodization: Active Rest
- individuals are psychologically and physiologically fatigued after long season
- engage in active rest for at least 4 weeks
- train so as to not lose overall fitness but volume and intensity are low
29
Periodization and Exercise Professionals
- application not limited to high level athletes
- understanding principles can help prevent injuries
- understanding can also help shape rehab programs
30
Sample PRE Programs
- many approaches to PRE
- structure of program depends upon ultimate goal
- professionals are limited only by understanding of underlying basic sciences and creativity
31
DeLorme and Watkins
- fathers of PRE
- same number of reps but increase % of RM from 50 to 75 to 100 over three sets
- training frequency 3d/wk
- rest period between sets 1-2 minutes
- rest between workouts 48 hrs
- resistance exercises may remain constant or be mixed
32
Oxford and Zinovieff
- regressive resistance exercise
| - start at 1 RM then decrease % of RM from 100 to 75 to 50 for 3 sets with the same amount of reps
33
Aggressive Resistance Training Programs
- used when maximal strength or muscular hypertrophy is desired
- lesser emphasis on muscular endurance
- common in competitive weightlifting, football, track and field, and bodybuilding
34
Sample Maximal Strength Program
- 4d/wk
- rest 3-5 min between sets
- rest 72 hours between body parts (legs: M and R, chest T and F)
- lower reps because of heavier weight trying to build bigger muscle
35
Sample of Bodybuilding Program
- 4d/wk
- rest 1 min between sets
- rest 72 hours between body parts
36
Daily Adjusted Progressive Resistance Exercise (DAPRE)
- form of periodization used particularly in rehab applications
- 4 sets per exercise
- set 1: 1/2 working weight: 10 reps
- set 2: 3/4 working weight: 6 reps
- set 3: full working weight: max
- set 4: adjusted working weight: max
- look at chart for guidelines on page 15
37
Circuit Training
- employs PRE: may also include calisthenic exercises
- valued for capacity to improve muscular strength and endurance for large groups
- system produces positive changes in general fitness, muscular strength and endurance, motor performance
38
Characteristics of Circuit Training
-based on premise that individual must do same amount of work in shorter time period
-variations exist but all have common factors...
-use of PRE
-use of physical conditioning and/or apparatus exercises
-time factor in which circuit must be completed
(common in cardiac rehab)
39
Setting Up a Circuit Training Program
- select number and type of activities for their functional carryover
- consider worth of each for promoting balanced musculoskeletal fitness
- set up 6-12 stations, each with a specific exercise
- plan circuit so trainee can complete circuit without undue fatigue
- system easily lends itself to handling large groups efficiently
- entails some preliminary planning but requires little ongoing coordination
- clients often find it motivating-can compete against time, self or teammate
- particularly useful method for weight machines
40
Implementing a Circuit Training Progarm
- thoroughly familiarize each client with motion to be done at each station
- perform a time trial to ascertain time needed to complete 1 to 3 laps of a circuit
- clients progress immediately from one station to the next: target time may be assigned, usually 1/3 lower than initial time trial
- weight exercises usually performed 50 to 70% of RM
- resistance usually estimated for initial trial
- may be easily changed for emphasis or client fun
- want muscular strength but really emphasize muscular endurance
41
Sample Circuit Training Program
- to be performed continuously from exercise to exercise without rest
- 2-3 d/wk
- number of circuits 2-3
- rest between sets .5-2 min
- rest period between workouts 48 h
42
Clinical Guidelines for General REsistance Exercise
- PRE programs address all types of muscular actions: isometric, isotonic, isokinetic
- perform systems review before starting
- prescribe at level appropriate for client
- integrate appropriate warm up and cool down
- program must have some motivational appeal
43
ACSM Recommendations for PRE
- perform minimum of 8-10 exercises that train the major muscle groups
- workouts should not be too long
- perform one set of 8-12 reps to point of volitional fatigue
- more sets may elicit greater strength gains but additional improvement is relatively small
- perform at least 2 days a week
- adhere closely to specific exercise techniques
- elderly clients should perform the exercises in maximum ROM that does not elicit pain or discomfort
- perform exercises in a controlled manner
- maintain a normal breathing pattern
- exercise with a training partner when possible
44
ACSM Recommendations for Warm-Up Exercises
- perform 12-15 reps with no weight before workout set with 30s to 4 m of rest before workout set
- specific warm-up is more effective for weight training than general warm-up
- no warm up set is required for high rep exercises: not as intense, serve as warm up themselves
- perform a 2nd warm up if joints and muscles involved may be more susceptible to injury
