Strength Testing - EXSC216 Study Guide PDF

EXSC216 Strength Testing 1 Content Strength & Strength Endurance Assessment National Sports Science Quality Assurance program NSSQA protocols Validity & Reliability Norms Predictive equations Scaling...

EXSC216 Strength Testing 1 Content Strength & Strength Endurance Assessment National Sports Science Quality Assurance program NSSQA protocols Validity & Reliability Norms Predictive equations Scaling 2 Why Is Assessing Strength Important? Measures of strength strongly correlated with athletic performance Discriminator of performance level in multiple sports Optimise program design Protective effect Assess effectiveness of training program Consider absolute vs relative strength Contraction mode specificity maximal strength v power 3 Discriminator of Performance Level 4 Strength Training for Endurance? Not just for “Strength” sports 5 6 7 Part 2 9 Testing Time of day Pre test training Pre test nutrition & hydration Exercise order Explosive before max strength Validity Reliability Calibration Reporting 10 Force-Velocity-Power 11 Harris et al 2006 Type of test? High force – low velocity E.g., ??? Low force – high velocity E.g., ??? Moderate force – moderate velocity E.g., ??? 12 Specificity – What are you testing? SAID Principle – Specific Adaptations to Imposed Demands Monitoring impact of training 13  “Guide” Relative Strength In Different Movements based off 1RMs Baker ‐ ASCA Level 2 14 Validity and Reliability Vital for data interpretation Simple concepts, should be clearly understood 15 Validity How is it assessed? r = 0.92 Compared to a ‘gold standard’. Beep test example  Ramsbottom, Brewer and Williams (1988) 16 Reliability How is it assessed? Multiple, repeat tests in the same condition Same day – intra-day reliability Different day – inter-day reliability Example of magnetic stimulation to the femoral nerve 17 Test Validity: Military Example – Jobs? Infantry Packs often > 40 kg Marching with packs often > 5 km Tank Crew Frequent shell loading ~20 kg per shell Clerk Frequent desk operations 18 Military Example – continued. Biased toward lighter individuals No ‘strength’ assessment Scaled for age and sex Every job, same tests 19 Military Example – new, proposed tests Basic level for all soldiers Clerks may need to be deployed Assess key capacities E.g., strength No scaling “Level” based on job demand 20 Part 3 21 What are we testing? Maximum Dynamic Strength: Maximum force that can be generated in a single effort against an external resistance Can be assessed in a number of ways 22 Types of Strength Testing Maximum Dynamic Strength Isokinetic Isometric Isoinertial Origins: ísos = ‘equal’ kinetikos = ‘to move’. metricos = ‘measure’ inertia = ‘resistance of physical object’ 23 Why not isotonic? What is it? ísos = ‘equal’ tonic = ‘tension’ But: Tension = changes through ROM isoinertial = more accurate 24 Brughelli & Cronin 2007 Equipment Isometric testing Force plate & immovable bar Other measurement device Isokinetic testing Dynamometer Isoinertial testing Barbell/db Weight plates 25 Isokinetic Dynamometry Constant angular velocity Peak/average force Popular clinically Used in research Assess asymmetry Criticised for lack of performance specificity but may be useful Ham/Quad Ratio… 26 Isometric Assessment Characterised by muscle actions that result in no change in joint angle Assess peak force & RFD Require subjects to produce max force against Strain gauge Cable tensiometer Force platform Load cells 27 Isometric mid-thigh pull: A popular test 28 Conducting an IMTP Test 29  Something’s not right IMTP Norms here… Physiological Tests For Elite Athletes‐2nd Ed 30 Other results: Body Mass IMTP IMTP Sport Sex (kg) (N) (N.Kg-1) Track Cycling Male (n=1) 71.8 3488.9 48.6 (Olympic Medalist) Motorbike Male (n=3) 72.9 3385.2 46.5 Weightlifting Male (n=3) 89.3 4526.3 50.7 (AUS National) Male (n=6) 78.8 3320.3 42.1 Tennis (National/International) Female (n=2) 65.3 2249 34.4 31 Other Isometric Tests Hip abduction & adduction Shoulder (ASH/IR/ER) Back extension Grip strength Groin Squeeze Iso Push Up 32 Isoinertial Testing Constant gravitational load throughout the movement Repetition Maximum (RM) testing: generally involve large muscle mass movements for a specified number of repetitions Requires ability to handle maximal loads 33 Part 4 34 Strength Testing Guidelines General warm up/Stretch?? Specific warm up 40-60% specified RM for up to 10 reps Minimum 2 min recovery 60-80% specified RM for max 5 reps Minimum 2 min recovery 90% specified RM for max 3 reps 5 minute rest Test sets 35 Strength Testing Guidelines Other considerations: Experience Strength E.g., Lifter who squats 200 kg Intensity/Reps 40% x 8 60% x 5 90% x 3 Test Set #1 Load (kg) 80 120 180 200? Stronger lifters may require more warmup sets Intensity/Reps 35% x 8 55% x 5 70% x 3 85% x 1 90% x 1 Test Set #1 Load (kg) 70 110 140 170 190 200 36 Strength Testing Guidelines Technical errors Lowering and lifting in a continuous manner No > 3s pause between reps Max 5 min recovery between sets Minimum weight increments dictated by Equipment availability Test movement TE/CV% 37 Strength Testing Challenges Questions you should ask yourself: Where do you start? E.g., Specific loads? Exercises? Safety? Are they ready for this? Why are you testing? What’s the goal? Is it actually necessary? 38 What movements? Bench press Bench pull Chin ups/Lat pulldown Incline leg press Single leg press Squat Others? 39 Max Strength Reliability 1RM 1RM 1RM Squat Bench Power Press Clean ICC 0.97 0.98 0.94 CV% 3.5% 2.8% 4.8% Physiological Tests For Elite Athletes‐2nd Ed 40 Determining Change From previous: What degree of change is required to be practically important? Individually Group Need to make an assessment of the magnitude of change and consider the “noise” in the test 41 Test Sensitivity Ability of a test to detect smallest practically important change Smallest worthwhile change calculated as: 0.5 CV% or 0.2 x between subj SD Subject VJ (cm) Trial 1 VJ (cm) Trial 2 1 65 64 2 63 64 3 66 65 4 62 63 5 64 65 SD 1.58 0.84 X 0.2 0.32 0.17 42 0.25 Individual Comparisons Example 1RM Squat CV:3.5% First Score Second Score Change Rating 100kg 102.5 2.5kg stable 100kg 105 5.0kg higher 100kg 95 ‐5.0kg lower 43  Max Strength Norms Source: Sport: n (Sex) Back Squat (RM) Daniels et. al., 2019 Professional Rugby 21 (M) 199 ± 25 (3RM) Freeston et. al., 2016 Well Trained 12 (M) 159 ± 49 (1RM) Caia et. al., 2013 Elite AFL 18 (M) 131.4 ± 18.1 (1RM) Caia et. al., 2013 Sub‐elite AFL 12 (M) 121.0 ± 16.7 (1RM) Ooi et. al., 2009 Elite Malaysian Badminton 12 (M) 143.2±17.3 (1RM) Ooi et. al., 2009 Sub‐elite Malaysian Badminton 8 (M) 129.9±14.1 (1RM) Dridd et. al., 2015 Elite European Judo Players 5 (M) 179 ± 6 (1RM) Dridd et. al., 2015 Sub‐elite European Judo Players 5 (M) 170 ± 5 (1RM) AIS Basketball 10 (M) 115 ± 17 (3RM) AIS Basketball 14 (F) 75 ± 14 (3RM) AIS Rugby League 14 (M) 99 ± 24 (3RM) Senior National Volleyball (90deg) 9 (M) 139 ± 30 (3RM) Physiological Tests of Junior National Volleyball (90deg) 7 (M) 115 ± 25 (3RM) Elite Athletes (AIS, AIS Netball (parallel) 12 (F) 67 ± 15 (3RM) Tanner and Gore, Elite Judo 14 (M) 121 ± 36 (3RM) 2013) Elite Judo 11 (F) 92 ± 14 (3RM) NTID Judo 16 (M) 86 ± 33 (3RM) NTID Judo 14 (F) 66 ± 15 (3RM) Senior Naitonal Rowing 10 (M) 137 ± 14 (3RM) 44 Part 5 45 Predictions!? 46 Prediction Equations Not all subjects are capable of performing 1RM testing Prediction equations allow estimation of 1RM from sub- maximal repetitions Numerous population specific equations Multiple ways to predict 47 48 Repetition Max Calculation We know 1 RM, predict 6 RM: Weight Lifted x Percent RM as decimal = We know 8 RM, predict 1 RM: Weight Lifted ÷ Percent RM as decimal = 49 Reps to fatigue 50 Velocity-based predictions Using barbell velocity to: Predict 1RM Measuring barbell velocity during concentric phase of movement Banyard et al (2017) 51 Limitations with Velocity Tests? Not all the research ends up with the same results Banyard et al (2017) ( Relationship post-training intervention Stable following training: Muscular Endurance Some sports require high force production for long durations Generally: Low load/No load (BW) Absolute / Relative strength endurance Multi-joint movements e.g., Chins, Leg Press, etc. Issues? http://s1.reutersmedia.net/resources/r/?m=02&d=20080811&t=2&i=5533069&w=780&fh=&fw=&ll=&pl=&sq=&r=2008‐ 55 08‐11T173320Z_01_PEK263334_RTRUKOP_0_PICTURE0 Part 6 - Final 56 Big V Small 190 kg C + J 263.5 kg C + J 60 kg BW 163.5 kg BW 57 Body Weight Considerations Important issue in max strength 213 kg Snatch assessment 263.5 kg C + J If not taken into account then there can Sinclair: 480.25 be an over or underestimation of max strength depending on the lift External load favours heavier athletes Body weight movements favour lighter 163.5 kg athletes Scaling relative to body weight (strength/body mass) common but result may not be equal for lifters of 152.5 kg Snatch different mass (Cleather 2006) 190 kg C + J Sinclair: 507.25 Other scales have been developed 58 60 kg Body Weight Correction “Wilks” formula used in Powerlifting Lift weight x body weight conversion factor E.g. 69.3 kg male conversion factor is 0.7552 “Siff” formula for Olympic and other lifts “Sinclair” formula used in Weightlifting and adjusted every Olympic year based on World Record totals over previous years From Previous: 276.79 263.93 59 Coefficients 60 Allometric Scaling Scaling according to body mass attempts to account for influence of muscle mass on performance Known as “ratio” scaling (i.e. strength/BM) Assumes a linear relationship between BM and performance Allometric scaling involves raising BM to the power of 0.67 (BM0.67) Based on theory that force & power increase with BM to the power of 2/3 61