Ex Phys - Adaptations Resistance Training

Resistance training

a systematic program of exercises involving the exertion of force against a load, used to develop strength, endurance, and/or hypertrophy of the muscular system

Developing a program: 1

goal identification

-desired outcome, component of muscular fitness to be stressed, mode of contraction, muscle groups

training principles of goal identification

specificity + individualization

Developing a program: 2

evaluation of initial strength or muscular endurance levels

-each muscle group to be used, proper lifting techniques

training principles of evaluation

specificity

Developing a program: 3

determination of the training cycle (periodization)

-prevention of boredom, peaking

training principles of periodization

adaptation, progression/retrogression/plateau, individualization

Developing a program: 4

determination of the training system

-exercises to be included, load

training principles of training system

specificity, overload, individualization, warmup and cool down

Specificity

muscle groups (single vs multi joint)

type of contraction (static, dynamic, velocity, ROM)

overload

intensity (relative load, absolute load)

Volume (total # of reps, reps x sets, reps x sets x intensity)

Frequency

rest intervals

Rest/recovery/adaptation

at least 1 day of rest between sessions for same muscle group

alternate heavy and light days

high volume training may require 72 hour rest breaks

progression

gradual

strength (increase weight, may need to decrease reps initially)

endurance (keep weight constant and increase reps)

increase training volume by 2.5-5% (elite athletes maybe more than 5%)

maintenance

like aerobic maintenance, intensity is key, but total volume can decrease

retrogression/plateau/reversibility

If not increase in gains despite progression of program, assess for overtraining; gains will be lost if training ceases

warmup and cooldown

can use similar activities as used for aerobic warm up; should also perform specific weight training exercises with a lower weight as a warm up and cooldown; stretching after cooldown

muscle function

increased strength, endurance, power

*takes more for legs to achieve overload

muscle size and structure

adaptations influenced by genetics, age, sex, and training protocol

-increase in CSA of 7-15% after 10-14 wks of training (hypertrophy of all 3 fiber types, greatest in FG)

-increase in total contractile protein, size and # of myofibrils per fiber, amount of CT surrounding muscle fibers

hyperplasia

addition of new muscle fibers

-controversial, not huge contributor to increase in CSA

neural adaptations

increased neural drive, increased MU synchronization, inhibition of GTOs, coordination of agonists/antagonists/synergists

*early increase in strength is due to neural adaptation

metabolic adaptations

increased ability to produce ATP

increase in PC & glycogen stores

increased activity of creatine phosphokinase

hormonal adaptations

neuroendocrine system is crucial for catabolism/anabolism

conflicting information on training adaptations

male vs female adaptations

both demonstrate increase in strength, CSA, and less fatiguability with training

adaptations in children

-strength gains of ~30% are typical following short term resistance training programs

-increases in strength seem fairly consistent between prepubescent and adolescents

-no apparent difference in the relative strength increases between boys and girls

adaptations in elderly

-significantly higher increases in strength in males

-can see increase in muscle mass in in elderly

-increased independence, decreased risk of falls, etc

muscular adaptations to aerobic endurance training programs

1. increase in SO fiber size

2. possible transition in FG fibers to FOG (metabolic change)

muscular adaptations to concurrent training

-strength gains appear to be attenuated when aerobic training is combined with strength training (highly dependent on periodization)

mechanisms of concurrent training

overtraining, residual fatigue from aerobic limits resistance training, molecular mechanisms (cell signaling, stimulation of different pathways may inhibit/interfere with certain pathways)

adaptations to detraining

-strength is maintained longer than many other training adaptations

-5-30% decrease in strength reported with 30-32 weeks of detraining

-females more susceptible to detraining than males