Low Intensity Alternatives for Strength and Hypertrophy

Transcription

1 Low Intensity Alternatives for Strength and Hypertrophy Jacob M. Wilson, PhD, CSCS*D Human Performance laboratory University of Tampa, Tampa, FL Traditional Techniques The American College of Sports Medicine (ACSM) recommends lifting a weight of at least 70% 1RM to achieve muscular hypertrophy as it is believed that anything below this intensity rarely produces substantial muscle growth. 1

2 But Why!? Moderate intensity exercise performed near failure appears to maximize metabolic stress and near the end of the set maximally recruit motor units. Intensity Zone Muscle fiber hypertrophy appears to cluster at around % in type I and type II fibers Fry et al. Alternative Methods Blood flow restriction training, as the name implies, involves decreasing blood flow to a working muscle, by application of a wrapping device, such as a blood pressure cuff. 2

3 Results Low Intensity (LI) results in no muscle growth, but when occluded it results in substantial growth HYPERTROPHY Walking = Growth!? 3

4 Hypoxia Increases Growth Factors and Satellite Cells Loenneke, Wilson 2009 Metabolic Stress 290 % vs. 100 tradi onal training Takarada et al

5 Motor Unit Recruitment Motor Unit Recruitment Tanaka and Naokata Ishii Yudai Takarada, Haruo Takazawa, Yoshiaki Sato, Shigeo Takebayashi, Yasuhiro 2000 vascular occlusion on muscular function in humans Cell Swelling Theory 5

6 Cell Swelling Vatus lateralus thickness Vatus Intermedialis Femur Thickness pre occlusion Wilson, Lowery, Joy, Loenneke 2013 Cell Swelling Vatus lateralus thickness Vatus Intermedialis Femur Thickness post occlusion with wrap Wilson, Lowery, Joy, Loenneke 2013 Training Variables METALLICA + OCCLUSION Exercise Mode Volume Device? Frequency BODYBUILDING CONTEST PREP IMMEDIATELY AFTER USING BFR FOR THE FIRST TIME! 6

7 Modality Should you progress from one to the other? Loenneke, Wilson, 2011 Frequency 1.5 Strength 2 3 days 1.0 Effect Size Loenneke, Wilson, Days Per Week Rest Period Length 1.5 Strength 1.0 Effect Size Loenneke, Wilson, s 60 s Rest Period Length Between Sets 7

8 Wrapping Pressure Complete arterial restriction lowers total volume, and increases the rate of pain and perceived exertion Cuff Width Wide Cuff = Lower arterial occlusion Pressures. Loenneke et al Cuff Width SIGNIFICANTLY REDUCED HYPERTROPHY AT THE LEVEL OF CUFF APPLICATION (FIG. 2), SUGGEST THATHIGH COMPRESSION AND SHEAR STRESS UNDER THE CUFF HAD A DELETERIOUS IMPACT ON THE MUSCLE. 230 MM HG + WIDE CUFF Kacin and Stazar

9 Wide Cuff = Lower Volume Rossow et al Material Material may not matter as much. Loenneke et al (Unpublished Observations) 9

10 Device = $$ 10 20,000 Practical Blood Flow Restriction Loenneke et al Practical Blood Flow Restriction Loenneke et al

11 Example on Arms With Wrist Wraps How Do I Wrap Vein Artery No Wrap Wilson, Lowery, Joy et al How Do I Wrap Artery Wrapped 7 out of 10 perceived Pressure Wilson, Lowery, Joy et al

12 How Do I Wrap Wrapped 10 out of 10 perceived Pressure Wilson, Lowery, Joy et al Results: Skeletal Muscle Activation Wilson, Lowery, Joy et al Results: Metabolic Stress Wilson, Lowery, Joy et al

13 Results: Muscle Swelling Wilson, Lowery, Joy et al Chronic Practical BFR 24 resistance trained males divided into two groups Group BFR First Performed low intensity pbfr for 4 weeks and then high intensity (>70 % 1 RM) for 4 weeks. Group BFR Second Performed 4 weeks of high intensity followed by BFR for 4 weeks Lowery, Joy, Wilson, Loenneke, Dudeck In Review Chronic Practical BFR Figure'2.0:'Muscle'thickness'Weeks'0,4,and'8'in'' both'bfr>hi'and'hi>bfr.' BFR>HI'Group' HI>BFR'Group' Lowery, Joy, Wilson, Loenneke, Dudeck In Review *'Significantly'greater'than'baseline,'p<.05'' #'Significantly'greater'than'Week'4,'p<.05' 13

14 5/22/2013 Chronic Practical BFR Figure'2.0:'Muscle'thickness'Weeks'0,4,and'8'in'' both'bfr>hi'and'hi>bfr.' BFR>HI'Group' HI>BFR'Group' Lowery, Joy, Wilson, Loenneke, Dudeck In Review *'Significantly'greater'than'baseline,'p<.05'' #'Significantly'greater'than'Week'4,'p<.05' Contraction Type: Not About Damage Yasuda, Loenneke 2012 Injury Rehab? A. Blood Flow Restricted Progression P1 P2 P1. Bed Rest + BFR P3 P2. Walking + BFR P3. Resistance + BFR Muscle Size Normal Progression P1 P2 P1. Bed Rest P3 P2. Walking + Crutches P3. Walking Muscle Size 14

15 Injury Rehab OSTEOCHONDRAL FRACTURE REQUIRING SURGERY 30 DAYS OF BLOOD FLOW RESTRICTION, INJURY HAD HEALED ITSELF NO SURGERY SAFE- READ OUR PAPER FOR MORE DETAILS! 15

16 Questions? 16