Predicting muscular strength using demographics,skeletal dimensions,and body composition measures

The purpose of this study was to develop an equation to predict strength for seven common resistance training exercises using anthropometric and demographic measures.One-hundred forty-seven healthy adults(74 males,73 females,3512 yr,17410 cm,8819 kg)volunteered to participate.Body composition values(regional/total)and body dimensions were assessed using dual-energy x-ray absorptiometry(DEXA).Subjects underwent the following maximal strength assessments:Leg Press,Chest Press,Leg Curl,Lat Pulldown,Leg Extension,Tri-ceps Pushdown,and Biceps Curl.Multiple linear regression with stepwise removal was used to determine the best model to predict maximal strength for each exercise.Independent predictor variables identified(p<0.05)were height(cm);weight(kg);BMI;age;sex(0=F,1=M);regional lean masses(LM,kg);fat mass(FM,kg);fat free mass(FFM,kg);percent fat(%BF);arm,leg,and trunk lengths(AL,LL,TL;cm);and shoulder width(SW,cm).Analyses were performed with and without regional measures to accommodate scenarios where DEXA is un-available.All models presented were significant(p<0.05,R^(2)=0.68-0.83),with regional models producing the greatest accuracy.Results indicate that maximal strength for individual resistance exercises can be reasonably estimated in adults.

Wearable positive end-expiratory pressure valve improves exercise performance

We tested a PEEP(4.2 cmH_(2)O)mouthpiece(PMP)on maximal cycling performance in healthy adults.Experiment-1,PMP vs.non-PMP mouthpiece(CON)[n=9(5♂),Age=30±2 yr];Experiment-2,PMP vs.no mouthpiece(NMP)[n=10(7♂),Age=27±1 yr].At timepoint 1 in both experiments(mouthpiece condition randomized)subjects performed graded cycling testing(GXT)(Corival®cycle ergometer)to determine VO_(2peak)(ml*kg*min^(-1)),O2pulse(mlO2*bt^(-1)),GXT endurance time(GXT-T(s)),and VO_(2)(ml*kg*min^(-1))-at-ventilatory-threshold(VO_(2)@VT).At timepoint 272 h later,subjects completed a ventilatory-threshold-endurance-ride[VTER(s)]timed to exhaustion at VO_(2)@VT power(W).One week later at timepoints 3 and 4(time-of-day controlled),subjects repeated testing protocols under the alternate mouthpiece condition.Selected results(paired T-test,p<0.05):Experiment 1 PMP vs.CON,respectively:VO_(2peak)=45.2±2.4 vs.42.4±2.3 p<0.05;VO_(2)@VT=33.7±2.0 vs.32.3±1.6;GXTTTE=521.7±73.4 vs.495.3±72.8(p<0.05);VTER=846.2±166.0 vs.743.1±124.7;O2pulse=24.5±1.4 vs.23.1±1.3(p<0.05).Experiment 2 PMP vs.NMP,respectively:VO_(2peak)=43.3±1.6 vs.41.7±1.6(p<0.05);VO_(2)@VT=31.1±1.2 vs.29.1±1.3(p<0.05);GXT-TTE=511.7±49.6 vs.486.4±49.6(p<0.05);VTER 872.4±134.0 vs.792.9±122.4;O2pulse=24.1±0.9 vs.23.4±0.9(p<0.05).Results demonstrate that the PMP conferred a significant performance benefit to cyclists completing high intensity cycling exercise.