Repetition Maximum Testing - Ex Testing

Dynamic Strength

• Consists of muscle actions that are concentric and/or eccentric with elimination of the isometric phase

• Speed of movement is variable through out the movement

  • Load does not change

Factors affecting Speed of the Movement

• Biomechanical

• Physiological

• Anatomical

Rationale for Testing Strength

• Purposes related to health and performance

• Important to evaluate in order to determine:

  • Training program

  • Monitor training progress

Direct Measurement from 1 RM

• Maximal weight lifted in the prescribed manner only one time

Indirect Measurement from 1 RM

• Estimates max effort by knowing the submaximal repetitions to failure for any given weight lifted

  • ~75-90% RM to predict 1-RM

  • Possibly as low as 60% RM

  • 3, 5, 10, repetitions are most utilized

Linear vs Curvilinear Relationship

• Linear has a 2.5% change for each petiton

  • Depending on reps you either go up or go down

• Curvilinear has a decrease in 1-RM at low rep range and has an increase in 1-RM at a higher rep range

Linear RM Example

• 8-RM = 100 lbs

• 8 reps x 2.5% = 20% weight added

• 1-RM: 100 × 1.20 = 120 lbs

Curvilinear Relationship Example

Accuracy of RM Testing

• Strength scores vary due to biological variability

  • Changes by 2-18%

  • Due to fatigue, sleep, stress, nutrition, time of day

• Test re-test variation of direct and predicted is 5-15%

  • Day 1 BP: 100 lbs

  • Day 3 BP: 85-115 lbs

    • Use an average of a few trials of separate occasions

• 225 lbs BP test to failure is a valid test to predict 1-RM in college football players

• Large range for estimating predicted RM range

  • 60-90% variation per person based off initial strength and resistance training

• Indirect assessment appear to be more accurate with smaller muscle groups and often overestimate 1-Rm in exercises involving large muscle groups

Protocols for Measuring Differing RM

• Typically always ≤ 10 reps

• Highest accuracy from ranges < 6 reps

  • Highest reliability and validity

• Most common = 3 RM

• 10-RM is often used for strength-endurance occasions

Effect of Rest Interval Length on RM Testing

• Time taken between sets

• Classified into 3 categories

  • Short: ≤30 secs

  • Moderate: 60-90 secs

  • Long: ≥ 3 mins

• Type or RIL has a distinct effect on short-term training session

Short Rest Interval

• High metabolic accumulation (Pi, ADP, lactate, H⁺) HR, O₂

• Low mechanical tension

Moderate Rest Interval

• Around equal metabolic accumulation and mechanical tension

Long Rest Interval

• Low metabolic accumulation, HR, O₂

• High mechanical tension

• Sustained ability to maintain mechanical tension (force) for longer periods of time

Results of a 10-RM (75% of 1-RM)

• Training weight and volume are reduced proportionally as RI length is reduced

• Fatigue rate is significantly correlated with metabolic response

  • O₂ > 10-RM compared to 5-RM

• When using loads of 10-RM expect the lifter to fatigue by as much as 20% with 3 mins rest

Results of 5-RM (85% 1-RM)

• Training weight and volume are close to maintained when >3 min RI

• When using loads of 5-RM optimal to use 3-5 min rest to maintain subsequent set mechanical tension

Substrate Replenishment Durations

• Length of rest intervals dictates magnitude of recovery that takes place between sets and exercises

• Replenishment of ATP-PCr system buffering of H⁺, and removal of lactate all need to occur

  • Shorter intervals limit amount of recovery between sets

  • Individual performance subsequent sets in a pre-fatigue state

  • Reduced loading capacity = slower rate of strength increase

• PCr

  • After 20 seconds 50% of PCr replenished

  • After 3 mins 85% of PCr replenished

Moderate vs Long Rest Periods

• Compared to longer rest periods moderate rest periods of ~90 seconds showed:

  • Increased blood lactate, decreased pH

• Effect on loading

  • Using a 60-sec RI requires a reduction of 5-10% in each successive set for maintenance of prescribed repetition range

• 60-90 sec RI should not be permitted when trying to achieve a RM or confirm the RM on the subsequent set

Testing Order: Multiple tests in one session

• Key limitation to traditional guidelines of MJ prior to SJ

  • Ignores that fatique occurs in two places

    • Central nervous system

    • Inside the local muscle

  • CNS fatigue prevents full motor unit recruitment from being reached

• Acute studies show performance is compromised in exercise performed towards the end of a session regardless of size of muscle trained

  • Place exercises that most important for testing or the training sessions at the beginning

Which submax RM should I choose?

• Load that closely resembles training goals and energy system to be targeted

• Ex: 5-RM cannot be used to accurately estimate a 15-RM because of the divergence in energy system requirement

• A 5-RM while overestimate the load an individual can lift for 15-RM