Kinesiology Commons^™

In-Season Hip Thrust Vs. Back Squat Training In Female High School Soccer Players, Nicole A. Millar, Lauren M. Colenso-Semple, Robert G. Lockie, Risto H.J. Marttinen, Andrew J. Galpin

International Journal of Exercise Science

International Journal of Exercise Science 13(4): 49-61, 2020. The barbell back squat provides a highly effective training stimulus to improve lower body strength, speed, and power, which are considered key components of athletic performance in many sports. The barbell hip thrust exercise utilizes similar musculature, and is popular among practitioners, but has received far less scientific examination. The purpose of this study was to evaluate the effects of an in-season resistance training program with hip thrusts or back squats on physical performance in adolescent female soccer players. Fourteen players completed identical whole-body resistance training twice per week for 6 weeks, …

Post Exercise Hypotension Following Concurrent Exercise: Does Order Of Exercise Modality Matter?, Whitley J. Stone, Mark A. Schafer, Scott W. Arnett, Scott Lyons

International Journal of Exercise Science

International Journal of Exercise Science 13(2): 36-48, 2020. Cardiovascular (CV) and resistance training (RT) can moderate negative effects of aging, disease, and inactivity. Post-exercise hypotension (PEH) has been used as a non-pharmacological means to control and reduce BP. Few have evaluated PEH response following a bout of exercise combining CV and RT, whether or not there is an order effect, or if PEH continues when activities of daily living (ADLs) are resumed. Participants (N= 10) completed a non-exercise control, a graded exercise test (GXT), and two concurrent sessions (CVRT and RTCV). Each session was followed by a 60-minute …

Effects Of A Strength Training Intervention And Quality Of Life: Case Study On A Sedentary Adult Female, Lucas Frazier

Williams Honors College, Honors Research Projects

The purpose of the project is to evaluate physiological and quality of life changes in a

sedentary, senior-aged (55 or older) female using a six-week strength training

intervention. This case study will instruct how to perform a push-pull-legs split

routine by going to the gym three times per week. Prior to the six week intervention,

both quantitative and qualitative variables will be collected to assess baseline data,

including the subject’s resting heart rate, resting blood pressure, grip strength, one-

repetition maximum on seven whole body exercises (dumbbell bicep curl, tricep

pushdown, barbell bench press, wide-grip lat pull-down, seated dumbbell press, …

Comparison Of Single Leg Squat Variations On Lower Limb Muscle Activation And Center Of Pressure Alterations, Mary Grace Knoll, Mackenzie C. Davidge, Claire E. Wraspir, John A. Korak

International Journal of Exercise Science

International Journal of Exercise Science 12(1): 950-959, 2019. Following anterior cruciate ligament reconstruction, individuals experience inadequate functioning of the quadriceps and decreased muscular strength. Decreased function delays return to physical activity and increases potential for re-injury. While several squat variations exist, a new variation has emerged in rehabilitation. The purpose of this study was to compare muscle activation of the Vastus Lateralis (VL), Vastus Medialis (VM), Rectus Femoris (RF), Gluteus Maximus (GM), and anterior posterior center of pressure (AP displacement) alterations during a single leg squat variation (SLS variation) versus a traditional split squat using electromyography (EMG) in healthy active …

Effects Of Home-Based Exercise Training Systems, Combined With Diet, On Cardiometabolic Health, Christian K. Roberts, David E. Segovia, Eli Lankford

International Journal of Exercise Science

International Journal of Exercise Science 12(2): 871-885, 2019. The efficacy of exercise training systems designed to be used in the home on cardiometabolic outcomes remains largely unknown. This investigation included two studies. Study 1 tested the effects a multi-exercise pulley system(NordicTrack Fusion CST with video trainer) and Study 2 an incline trainer (NordicTrack X22i with video trainer), both combined with daily food provision, for 12-weeks on indices of cardiometabolic health. Study 1 enrolled 27 adults (11 men, 16 women, 33.8±4.4 years of age) and Study 2 enrolled 29 adults (11 men, 18 women, 40.8±12.5 years of age). Pre- and post-intervention …

Kinetic And Kinematic Characteristics Of Accentuated Eccentric Loading, John Wagle

Electronic Theses and Dissertations

The current investigation was an examination of the kinetic and kinematic characteristics of the back squat using accentuated eccentric loading (AEL) and cluster set programming strategies. Trained male subjects (age = 26.1 ± 4.1 years, height = 183.5 ± 4.3 cm, body mass = 92.5 ± 10.5 kg, back squat to body mass ratio = 1.8 ± 0.3) volunteered to complete four different load condition sessions involving traditionally loaded straight sets (TL), traditionally loaded cluster sets (TLC), AEL cluster sets (AEC), and AEL straight sets where only the first repetition of each set used eccentric overload (AEL1). The use of …

Effects Of Resistance Training Frequency On Muscle Function Adaptations Using A Multiple-Joint Eccentric Training Model, Joshua Crane

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Eccentric resistance training has been shown to be beneficial for improving multiple performance and health metrics. However, recommendations on eccentric training frequency have not been established. PURPOSE: To investigate the effects of volume-matched resistance training frequency comparing one versus three training days per week of isokinetic multiple-joint eccentric training on strength and lower body function adaptations during a 4-week training period. METHODS: Thirty recreationally-trained men and women were randomly assigned to either a high frequency (HF), three times per week, or low frequency (LF), once per week, training group for four weeks. A motor-driven isokinetic eccentric dynamometer was used for …

The Impact Of Power Training On Balance And Visual Feedback Removal, Juliana Bouton

Juliana Bouton

Factors Related To Average Concentric Velocity Of Four Barbell Exercises At Various Loads, Christopher A. Fahs, Julia C. Blumkaitis, Lindy M. Rossow

Faculty Scholarship

The resistance exercise load is the primarily determinant of the average concentric velocity (ACV) during a repetition. It is unknown whether individual factors such as training experience or anthropometrics also influence the ACV. Previous research has shown the ACV during the 1 repetition maximum (1RM) varies between exercises, but it is not clear whether ACV is different between exercises at various percentages of the 1RM. This information could provide practical guidelines for trainees using ACV to select training loads. Therefore, the purpose of this study was to determine whether training age, current training frequency, limb length, height, and relative strength …

A Comparison Between The Efficacy Of Traditional Periodization, Undulating Periodization, And Plyometric Training And Their Lasting Effects On Performance Outcomes In Youth Athletes. A Systematic Review And Meta-Analysis, Andre Mcintyre

Electronic Theses and Dissertations

Recreational and competitive youth (≤ 16 years old) sport participation over the years has increased in recent years. As a result of increased sport participation an emphasis on sport performance training and more particularly resistance training along with plyometric training have been on the rise. Resistance training and plyometric training can improve sports performance, rehabilitate injuries, prevent injuries, and enhance long-term health in adolescent athletes. Resistance training can be periodized numerous different ways, but the most popular training methods are traditional periodization, undulating periodization, and plyometric training. This systematic review and meta-analysis examined studies that compared traditional periodization, undulating periodization, …

Mind-Muscle Connection: Effects Of Verbal Instructions On Muscle Activity During Bench Press Exercise, Antonio Paoli, Laura Mancin, Matteo Saoncella, Davide Grigoletto, Francesco Q. Pacelli, Paola Zamparo, Brad J. Schoenfeld, Giuseppe Marcolin

Publications and Research

Different attentional foci may modify muscle activation during exercises. Our aim was to determine if it is possible to selectively activate the pectoralis major or triceps brachii muscles according to specific verbal instructions provided during the bench press exercise. 13 resistance-trained males (25.6±5.4 yrs, 182.7±9.1 cm, 86.4±9.7 kg) underwent an electromyographic signals acquisition of the sternocostal head, clavicular head of the pectoralis major, the anterior deltoid, and the long head of the triceps brachii (LT) during bench press exercise. Participants performed one non-instructed set (NIS) of 4 repetitions at 50% 1-repetition maximum (1-RM) and one NIS of 4 repetitions at …

Effects Of An Aqueous Extract Of Withania Somnifera On Strength Training Adaptations And Recovery: The Star Trial, Tim N. Ziegenfuss, Anurag W. Kedia, Jennifer E. Sandrock, Betsy J. Raub, Chad M. Kerksick, Hector L. Lopez

Faculty Scholarship

Withania somnifera (Ashwagandha) is an Ayurvedic herb categorized as having “rasayana” (rejuvenator), longevity, and revitalizing properties. Sensoril® is a standardized aqueous extract of the roots and leaves of Withania somnifera. Purpose: To examine the impact of Sensoril^® supplementation on strength training adaptations. Methods: Recreationally active men (26.5 ± 6.4 years, 181 ± 6.8 cm, 86.9 ± 12.5 kg, 24.5 ± 6.6% fat) were randomized in a double-blind fashion to placebo (PLA, n = 19) or 500 mg/d Sensoril^® (S500, n = 19). Body composition (DEXA), muscular strength, power, and endurance, 7.5 km cycling time trial, and clinical blood …

Muscle Adaptations To High-Load Training And Very Low-Load Training With And Without Blood Flow Restriction, Matthew B. Jessee, Samuel L. Buckner, J. Grant Mouser, Kevin T. Mattocks, Scott J. Dankel, Takashi Abe, Zachary W. Bell, John P. Bentley, Jeremy P. Loenneke

Faculty Scholarship

An inability to lift loads great enough to disrupt muscular blood flow may impair the ability to fatigue muscles, compromising the hypertrophic response. It is unknown what level of blood flow restriction (BFR) pressure, if any, is necessary to reach failure at very low-loads [i.e., 15% one-repetition maximum (1RM)]. The purpose of this study was to investigate muscular adaptations following resistance training with a very low-load alone (15/0), with moderate BFR (15/40), or with high BFR (15/80), and compare them to traditional high-load (70/0) resistance training. Using a within/between subject design, healthy young participants (n = 40) performed four …

Muscle Adaptations To High-Load Training And Very Low-Load Training With And Without Blood Flow Restriction, Matthew B. Jessee, Samuel L. Buckner, J. Grant Mouser, Kevin T. Mattocks, Scott J. Dankel, Takashi Abe, Zachary W. Bell, John P. Bentley, Jeremy P. Loenneke

Faculty Publications

An inability to lift loads great enough to disrupt muscular blood flow may impair the ability to fatigue muscles, compromising the hypertrophic response. It is unknown what level of blood flow restriction (BFR) pressure, if any, is necessary to reach failure at very low-loads [i.e., 15% one-repetition maximum (1RM)]. The purpose of this study was to investigate muscular adaptations following resistance training with a very low-load alone (15/0), with moderate BFR (15/40), or with high BFR (15/80), and compare them to traditional high-load (70/0) resistance training. Using a within/between subject design, healthy young participants (n = 40) performed four …

Resistance Training Does Not Induce Uniform Adaptations To Quadriceps, Gerald T. Mangine, Michael J. Redd, Adam M. Gonzalez, Jeremy R. Townsend, Adam J. Wells, Adam R. Jajtner, Kyle S. Beyer, Carleigh H. Boone, Michael B. La Monica, Jeffrey R. Stout, David H. Fukuda, Nicholas R. Ratamess, Jay R. Hoffman

Faculty and Research Publications

Resistance training may differentially affect morphological adaptations along the length of uni-articular and bi-articular muscles. The purpose of this study was to compare changes in muscle morphology along the length of the rectus femoris (RF) and vastus lateralis (VL) in response to resistance training. Following a 2-wk preparatory phase, 15 resistance-trained men (24.0 ± 3.0 y, 90.0 ± 13.8 kg, 174.9 ± 20.7 cm) completed pre-training (PRE) assessments of muscle thickness (MT), pennation angle (PA), cross-sectional area (CSA), and echo-intensity in the RF and VL at 30, 50, and 70% of each muscle’s length; fascicle length (FL) was estimated from …

The Effectiveness Of Myplate And Paleolithic-Based Diet Recommendations, Both With And Without Exercise, On Aerobic Fitness, Muscular Strength And Anaerobic Power In Young Women: A Randomized Clinical Trial, Collin Popp, Michelle Bohan Brown, Elliot D Jesch, William C. Bridges

International Journal of Exercise Science

International Journal of Exercise Science 11(2): 921-933, 2018. The purpose of this study was to evaluate the effectiveness of recommending a MyPlate or a Paleolithic-based diet, both with and without exercise, on aerobic fitness, strength, and anaerobic power over eight weeks. Participants (n=20) were randomized to one of four groups, (1) a MyPlate diet (MP), (2) Paleolithic-based diet (PD), (3) MyPlate and exercise (MP + Ex), and (4) Paleolithic-based diet and exercise (PD + Ex). The exercise included two days of unsupervised aerobic and resistance exercise. At baseline and final, absolute and relative peak oxygen consumption (absVO_2peak and relVO …

Repetition-To-Repetition Differences Using Cluster And Accentuated Eccentric Loading In The Back Squat, John P. Wagle, Christopher B. Taber, Aaron J. Cunanan, Matt L. Sams, Alexander Wetmore, Garett E. Bingham, Brad H. Deweese, Kimitake Sato, Charles A. Stuart, Michael H. Stone

Exercise Science Faculty Publications

The current investigation was an examination of the repetition-to-repetition magnitudes and changes in kinetic and kinematic characteristics of the back squat using accentuated eccentric loading (AEL) and cluster sets. Trained male subjects (age = 26.1 ± 4.1 years, height = 183.5 ± 4.3 cm, body mass = 92.5 ± 10.5 kg, back squat to body mass ratio = 1.8 ± 0.3) completed four load condition sessions, each consisting of three sets of five repetitions of either traditionally loaded straight sets (TL), traditionally loaded cluster sets (TLC), AEL cluster sets (AEC), and AEL straight sets where only the initial repetition had …

Behavior Of Heart Rate Variability After 10 Repetitions Maximum Load Test For Lower Limbs, Estêvão R. Monteiro, Jefferson S. Novaes, Aline G. Fiuza, Eduardo Portugal, Felipe S. Triani, Leonardo Bigio, Rudson Santos, Alexandre Palma, Victor G. Corrêa Neto

International Journal of Exercise Science

International Journal of Exercise Science 11(6): 834-843, 2018. The purpose of this study was to analyze the acute heart rate variability behavior after 10 repetitions maximum load test for back squat, leg press, leg extension, and leg flexion in normotensive subjects. Eight recreationally trained women (age: 21.8 ± 2.2 yrs; height: 167.6 ± 6.3 cm; weight: 61.6 ± 10.1 kg) performed two 10 repetitions maximum testing days with 48-hours rest between each one. Heart rate variability was measured in baseline and postexercise (15-, 30-, 45-, and 60-minutes) for time and frequency domain. A significant difference was identified in RMSSD_{ms …}

Peak Power Output In Loaded Jump Squat Exercise Is Affected By Set Structure, Nikolaj Koefoed, Mads Lerche, Bjørn K. Jensen, Pia Kjær, Sebastian Dam, Rasmus Horslev, Ernst A. Hansen

International Journal of Exercise Science

International Journal of Exercise Science 11(1): 776-784, 2018. A priority in strength and power exercise might be to train with as high quality as possible for the shortest possible duration. In this context, peak power output could reflect quality. Designing an exercise session as a cluster set structure, as compared to a traditional set structure, may be a way to obtain higher peak power output in the session. But it is unknown whether that is obtainable for non-elite individuals performing loaded jump squat exercise. The aim of the present study was therefore to test the hypothesis that peak power output …

Effect Of An 8-Week Eccentric Training Program On Strength And Balance In Older Adults, Samantha Johnson

International Journal of Exercise Science

International Journal of Exercise Science 11(3): 468-478, 2018. The purpose of the current study was to determine changes in balance and strength following an eccentric resistance training program in community-dwelling older adults who reported no history of falling. Participants (N = 14, 8 female, 6 male; age = 63.5 ± 2.0 years) completed an 8-week eccentric exercise training intervention on a commercially available eccentric step machine. Training included 2 training sessions per week, with a duration of 5 to 10 minutes and an intensity of 30 to 50% maximal eccentric strength. Single leg stance, 30-second repeated chair stand, timed …

Effects Of Strength Training Sessions Performed With Different Exercise Orders And Intervals On Blood Pressure And Heart Rate Variability, Sandro Lemos, Tiago Figueiredo, Silvio Marques, Thalita Leite, Diogo Cardozo, Jeffrey Willardson, Roberto Simão

International Journal of Exercise Science

International Journal of Exercise Science 11(2): 55-67, 2018. This study compared the effect of a strength training session performed at different exercise orders and rest intervals on blood pressure and heart rate variability (HRV). Fifteen trained men performed different upper body exercise sequences [large to small muscle mass (SEQA) and small to large muscle mass (SEQB)] in randomized order with rest intervals between sets and exercises of 40 or 90 seconds. Fifteen repetition maximum loads were tested to control the training intensity and the total volume load. The results showed, significant reductions for systolic blood pressure (SBP) for all sequences …

Force-Time Differences Between Ballistic And Non-Ballistic Half-Squats., Timothy J. Suchomel, Christopher Taber, Christopher J. Sole, Michael Henry Stone

Exercise Science Faculty Publications

The purpose of this study was to examine the force-time differences between concentric-only half-squats (COHS) performed with ballistic (BAL) or non-ballistic (NBAL) intent across a range of loads. Eighteen resistance-trained men performed either BAL or NBAL COHS at 30%, 50%, 70%, and 90% of their one repetition maximum (1RM) COHS. Relative peak force (PF) and relative impulse from 0⁻50 ms (Imp50), 0⁻90 ms (Imp90), 0⁻200 ms (Imp200), and 0⁻250 ms (Imp250) were compared using a series of 2 × 4 (intent × load) repeated measures ANOVAs with Bonferroni post hoc tests. Cohen's d effect sizes were calculated to provide measures …

Bilateral Deficit: A Comparison Between Upper-Body And Lower-Body Maximal Strength, James Lee Ramsey

Master's Theses and Doctoral Dissertations

Purpose: The study’s primary purpose was to determine if maximal unilateral strength is greater than maximal bilateral strength for the leg press and vertical dumbbell press exercises. The secondary purpose was to determine if blood glucose levels differ between the unilateral and bilateral conditions for the leg press exercise. Methods: Thirty college-aged volunteers reported on two separate occasions, 72 hours apart, for maximal strength testing. Blood glucose was obtained before and after strength testing for the leg press exercise. A paired samples t-test was conducted to determine significance (p < .05). Results: Participants were significantly stronger for the bilateral leg press; however, no significant differences were observed for the vertical dumbbell press exercise. No significant differences were observed in plasma blood glucose for the leg press exercise. Conclusion: Participants did not display a bilateral lateral deficit, which may have been a result of their resistance training prior to the study.

The Effects Of Resistance Training Volume On Skeletal Muscle Proteome, Ramires A. Tibana, Octávio L. Franco, Gabriel V. Cunha, Nuno M. F Sousa, Ivo V. Sousa Neto, Márcia M. Carvalho, Jeeser Alves De Almeida, James W. Navalta, Mariana O. Lobo, Fabricio A. Voltarelli, Rita C. Marqueti, João L.Q Durigan, Jonato Prestes

International Journal of Exercise Science

International Journal of Exercise Science 10(7): 1051-1066, 2017. Studies are conflicting to whether low volume resistance training (RT) is as effective as high-volume RT protocols with respect to promoting morphological and molecular adaptations. Thus, the aim of the present study was to compare, using a climbing a vertical ladder, the effects of 8 weeks, 3 times per week, resistance training with 4 sets (RT4), resistance training with 8 sets (RT8) and without resistance training control (CON) on gastrocnemius muscle proteome using liquid chromatography mass spectrometry (LC-MS/MS) and cross sectional area (CSA) of rats. Fifty-two proteins were identified by LC-MS/MS, …

Acute Effects Of Plyometric And Resistance Training On Running Economy In Trained Runners, Richard T. Marcello, Beau K. Greer, Anna E. Greer

All PTHMS Faculty Publications

Results regarding the acute effects of plyometric and resistance training (PRT) on running economy (RE) are conflicting. Eight male collegiate distance runners (21 +/- 1 years, 62.5 +/- 7.8 ml/kg/min V[Combining Dot Above]O2 peak) completed V[Combining Dot Above]O2 peak and 1 repetition maximum (1RM) testing. Seven days later, subjects completed a 12 minute RE test at 60% and 80% V[Combining Dot Above]O2 peak, followed by a PRT protocol or a rested condition of equal duration (CON). The PRT protocol consisted of 3 sets of 5 repetitions at 85% 1RM for barbell squats, Romanian deadlifts, and barbell lunges; the same volume …

Electromyographical Comparison Of A Traditional, Suspension Device, And Towel Pull-Up, Ronald L. Snarr, Ashleigh V. Hallmark, Jason C. Casey, Michael R. Esco

Department of Health Sciences and Kinesiology Faculty Publications

Strengthening muscles of the back may have various implications for improving functions of daily living, aiding in the transfer of power in throwing, and assist in injury prevention of the shoulder complex. While several versions of the pull-up exist, there is currently no literature comparing their differences. The purpose of this investigation was to compare the electromyographical activity of the latissimus dorsi, posterior deltoid, middle trapezius, and biceps brachii while performing three variations of the pull-up. Resistance-trained men and women (n = 15, age = 24.87 ± 6.52 years) participated in this study by performing traditional pull-ups, suspension device pull-ups, …

The Effect Of Acute Hyperglycemia On Muscular Strength, Power And Endurance, Franklin Lime-Ma, Joshua A. Cotter, Evan E. Schick

International Journal of Exercise Science

International Journal of Exercise Science 10(3): 390-396, 2017. The purpose of this study was to elucidate the impact of acute hyperglycemia on skeletal muscle strength, power, and endurance. Ten male collegiate athletes (age 21.5 ± 1.5 years, height 186 ± 2.03 cm, body mass 108.8 ± 7.6 kg) participated in 2 testing sessions, separated by 7 days and randomized for either high glucose (HG) or control (C) treatment conditions. HG consumed a high glucose drink (2 g glucose/kg body weight) while controls consumed an isocaloric nutrition bar (40% protein, 30% fat, and 30% carbohydrate). Blood glucose (BC) levels for HG …

The Effects Of Eccentric, Velocity-Based Training On Strength And Power In Collegiate Athletes, Samantha M. Dolezal, Tamra L. Llewellyn, Derek L. Frese

International Journal of Exercise Science

International Journal of Exercise Science 9(5): 657-666, 2016. The purpose of this study was to determine if combining velocity-based training with eccentric focus (VEB) and velocity-based training (VBT) results in power and strength gains. Nineteen men and women collegiate track and field athletes participated in this study. The subjects completed a 12-week intervention with either a VEB program or a VBT program. To determine the effectiveness of each program, the subjects completed four exercise tests before and after the training period: vertical jump, medicine ball put test, 1RM projected bench press and 1RM projected squat. There were no significant differences …

The Effect Of A Moderately-Low And High Carbohydrate Intake On Crossfit Performance, Kurt A. Escobar, Jacobo Morales, Trisha A. Vandusseldorp

International Journal of Exercise Science

International Journal of Exercise Science 9(4): 460-470, 2016. CrossFit is a metabolically demanding strength and conditioning method which performance may benefit from a carbohydrate (CHO)-rich diet. This study investigated the effect of three consecutive days of high CHO intake on CrossFit performance and corresponding metabolically -related variables in strength trained individuals. Eighteen subjects with a CHO intake of <6 g/kg/day were randomly assigned into a CHO (n = 9) or control (C) group (n =9) and underwent a 9-day training protocol. During days 1, 5, and 9, performance was measured as repetitions completed during a 12 minute CrossFit workout. Oxygen consumption (VO2), respiratory exchange ratio (RER), and blood lactate (BL) were also measured. Days 6-8, the CHO group increased CHO intake from <6 g/kg/day to 6-8 g/kg/day; the C group maintained their current intake of <6 g/kg/day. On days 6 and 7 both groups performed CrossFit workouts followed by a day of rest prior to day 9. There was a significant increase in repetitions completed in both groups in day 9 (vs. means score of day 1 + 5) (p = 0.002), but no differences between C and CHO groups (p = 0.111). However, the CHO group displayed a 15.2 repetition increase (+10.9%) in day 9, compared to 5.7 (+4.2%) by the C group. VO2, RER, and BL were not influenced by the experimental intervention. Our results suggest that the CrossFit-embraced practice of moderately-low CHO diets may be adequate in CHO during short periods of training, however, given the noted trend, extended training periods may be effected.

Eight Weeks Of Kettlebell Swing Training Does Not Improve Sprint Performance In Recreationally Active Females, Michael E. Holmstrup Ph.D., Brock T. Jensen Ph.D., William S. Evans, Emily C. Marshall

International Journal of Exercise Science

International Journal of Exercise Science 9(4): 437-444, 2016. The kettlebell swing (KBS), emphasizing cyclical, explosive hip extension in the horizontal plane, aligns with movement- and velocity-specificity of sprinting. The present study examined the effect of an eight-week KBS intervention on sprinting in recreationally-active females, in comparison to an eight-week intervention using the stiff-legged deadlift (SDL). Following a pre-testing session measuring 30 meter sprint and countermovement vertical jump performance, participants were divided evenly by sprint time into KBS (n=8) and SDL (n=10) cohorts. Following familiarization with the exercises, KBS met twice weekly to perform swings using the Tabata interval (20s work, …