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The purpose of this study was to examine the differences in braking and propulsion force-time characteristics and barbell velocity between traditional (TRAD) and accentuated eccentric loaded (AEL) back squats using various load combinations. Sixteen resistance-trained men participated in four separate testing sessions which included a one repetition maximum (1RM) back squat during the first session and three squat testing sessions. During the squat testing sessions, participants either performed sets of three repetitions of TRAD back squats each with 50, 60, 70, and 80% 1RM or performed the same loads with the addition of weight releasers that increased the total eccentric weight of the first repetition of each set to either 100 (AEL-MAX) or 110% 1RM (AEL-SUPRA). Braking and propulsion mean force, duration, and impulse as well as mean and peak barbell velocity were compared between each condition and load. Significantly greater braking impulses were produced during the AEL-MAX and AEL-SUPRA conditions compared to TRAD (p < 0.03) with small-moderate effect sizes favoring AEL-SUPRA. No other significant differences existed among conditions for other braking, propulsion, or barbell velocity variables. AEL-MAX and AEL-SUPRA back squats may provide a greater braking stimulus compared to TRAD squats; however, the propulsion phase of the movement does not appear to be impacted. From a loading standpoint, larger and smaller load spreads may favor rapid and maximal force production characteristics, respectively. Further research on this topic is needed as a large portion of the braking stimulus experienced during AEL back squats may be influenced by relative strength. [ABSTRACT FROM AUTHOR]

This study investigated the effects of the squat exercise combined with using barbells and elastic bands on muscle strength, body composition, and balance in working age men. A total of 24 men in working age between 18 and 39 years were randomly selected into 3 Groups using systematic sampling: (a) Combined Training using Elastic Band Weight at 35% (n = 7); (b) Combined Training using Elastic Band Weight at 20% (n = 8); and (c) Control Group (n = 9). The 2 Treatment Groups trained twice per week for 8 weeks. For each training session, squats combined with using elastic band repetitions per set of 4 sets (80% one-repetition maximum [1RM]) were performed in 0-4 weeks and (85% 1RM) in 5-8 weeks. Before and after 8 weeks of training, the participants were tested using the 1RM squat (SQ), Balance Error Score System (BESS), Vertical Jump Reach Test (VJT), and Body Composition. An analysis of the paired t-test revealed that the SQ, BESS, and VJT scores were significantly higher after training in the 2 Treatment Groups (P < 0.05). An analysis of covariance revealed that the SQ and BESS scores were significantly higher than those of the Control Group (P < 0.05). No significant differences were detected between the 2 Treatment Groups. The results suggest that combining barbell and elastic band exercise increases strength, balance, and power, and combined training with using a band among those who never performed resistance exercise via an applied load of bands that can be used to replace other weights. [ABSTRACT FROM AUTHOR]

Background: There is no clear agreement regarding the ideal rest interval and training intensity to optimize post-activation performance enhancement (PAPE) after barbell squat (BS). Therefore, the aim of this study was to investigate the effects of rest interval and training intensity on jumping performance due to PAPE. Methods: Searches were performed in PubMed, Web of Science, and EBSCO databases. We included studies that satisfied the following criteria: (1) eligible studies should be randomized controlled trials; (2) eligible studies should investigate the acute effect of barbell squat-induced PAPE on jump performance; (3) eligible studies should use countermovement jump, squat jump, or vertical jump as the outcome measure. Results: From 2518 search records initially identified, 19 studies were eligible for meta-analysis. Our meta-analysis results showed that BS had no significant effect on improving jumping performance due to PAPE (Cohen’s d = 0.09, p = 0.08). Subgroup analysis showed that rest interval between 0–1 min was detrimental to jumping performance (Cohen’s d = −0.33, p < 0.01), while rest intervals between 4–7 min (Cohen’s d = 0.31, p < 0.01) and 8-9 min (Cohen’s d = 0.26, p = 0.02) provided favorable jumping performance outcomes. In addition, low-intensity and moderate-intensity BS had no significant effect on jump performance, while high-intensity BS showed results consistent with rest interval. Conclusion: Our study indicated that both low-intensity and moderate-intensity BS failed to induce PAPE, and it is recommended that future studies use high-intensity BS to induce PAPE. A rest interval of 4–9 min had a beneficial impact on jump height, and an interval range of 4–7 min seems to be the best rest interval between conditioning activity and jumping performance. [ABSTRACT FROM AUTHOR]

Velocity-based training (VBT) is a method to monitor resistance training based on measured kinematics. Often, measurement devices are too expensive for non-professional use. The purpose of this study was to determine the accuracy and precision of the Apple Watch 7 and the Enode Pro device for measuring mean, peak, and propulsive velocity during the free-weighted back squat (in comparison to Vicon as the criterion). Velocity parameters from Vicon optical motion capture and the Apple Watch were derived by processing the motion data in an automated Python workflow. For the mean velocity, the barbell-mounted Apple Watch (r = 0.971–0.979, SEE = 0.049), wrist-worn Apple Watch (r = 0.952–0.965, SEE = 0.064) and barbell-mounted Enode Pro (r = 0.959–0.971, SEE = 0.059) showed an equal level of validity. The barbell-mounted Apple Watch (Vpeak: r = 0.952–0.965, SEE = 0.092; Vprop: r = 0.973–0.981, SEE = 0.05) was found to be the most valid for assessing propulsive and peak lifting velocity. The present results on the validity of the Apple Watch are very promising, and may pave the way for the inclusion of VBT applications in mainstream consumer wearables. [ABSTRACT FROM AUTHOR]

The purpose of this investigation was to compare concentric movement velocity (CMV) measured with the PUSH Band (v2.0) and a Vicon motion capture system (MC) during the back squat (SQ) and the bench press (BP) resistance exercises (RE). Twelve resistance-trained males (26.0 ± 5.5 years; 175.6 ± 4.9 cm; 96.3 ± 15.8 kg) completed ten repetitions at 50% of one-repetition maximum (1RM), and six repetitions at 75% 1RM for both BP and SQ. Four PUSH devices were utilized and attached to the subject's right forearm, the center barbell, left and right sides of the barbell. MC markers were placed on top of each PUSH device. An overall analysis using a series of least-squares means contrasts suggested CMV did not differ (p > 0.05) between measurement technologies when position, RE, intensity and repetitions were combined. PUSH exhibited the highest Intraclass Correlation Coefficients (ICC = 0.835–0.961) and Pearson Product-Moment Correlation Coefficients (r = 0.742–0.949) at the arm and center barbell locations when compared with MC. The measurement of CMV between MC and PUSH compares favorably during moderate (i.e., 50%) and high (75%) intensity SQ and BP RE. These data indicate individuals can use the PUSH band v2.0 to accurately monitor CMV within a RE set for SQ and BP RE. [ABSTRACT FROM AUTHOR]

This study investigated the effect of complex training with barbell thruster and medicine ball wood chop on Ippon-Seoinage throwing performance in male judo players. Eighteen male judo players 18 to 24 years of age were recruited to participate. The subjects were randomly assigned to 2 Groups. In the Experimental Group (n = 9), the subjects underwent complex training with barbell thruster and medicine ball wood chop program that consisted of 6 thrusters exercise at 85%1RM and then continued with 12 medicine ball wood chops at 10% of their body weight. The Control Group (n = 9) performed a normal complex training program that consisted of 6 squat exercises at 85%1RM that was followed by 12 squat jumps. Both Groups performed 4 sets of training per day twice a week for 6 weeks in addition to their normal. Before and after 6 weeks of training, the subjects' muscular strength, muscular power, and throwing velocity were determined. The data were analyzed using dependent and independent samples t-test. The statistical significance was set at a P-value of <0.05. The results showed that after 6 weeks of training, muscular strength and muscular power were significantly greater (P<0.05) in both Groups. Moreover, throwing velocity in the Experimental Group was a significantly higher (P<0.05) after training and significantly greater (P<0.05) than the Control Group at post-exercise. The findings indicate that the complex training with barbell thruster and medicine ball wood chop program was effective for improving throwing performance in judo players. [ABSTRACT FROM AUTHOR]

The back squat is one of the most effective exercises in strengthening the muscles of the lower extremity. Understanding the impact of footwear has on the biomechanics is imperative for maximizing the exercise training potential, preventing injury, and rehabilitating from injury. This review focuses on how different types of footwear affect the full-body kinematics, joint loads, muscle activity, and ground reaction forces in athletes of varying experience performing the weighted back squat. The literature search was conducted using three databases, and fourteen full-text articles were ultimately included in the review. The majority of these studies demonstrated that the choice of footwear directly impacts kinematics and kinetics. Weightlifting shoes were shown to decrease trunk lean and generate more plantarflexion relative to running shoes and barefoot lifting. Elevating the heel through the use of external squat wedges is popular method during rehabilitation and was shown to provide similar effects to weightlifting shoes. Additional research with a broader array of populations, particularly novice and female weightlifters, should be conducted to generalize the research results to nonathlete populations. Further work is also needed to characterize the specific effects of sole stiffness and heel elevation height on squatting mechanics. [ABSTRACT FROM AUTHOR]

Sagittal plane inclination of the trunk and tibia have been shown to independently modulate hip and knee extensor moments during squatting. The purpose of this study was to determine if the difference between sagittal plane trunk and tibia inclinations can be used to approximate the relative demand of the hip and knee extensors across a range of squatting conditions. Kinematic and kinetic data were obtained from 16 participants during 8 squat conditions in which trunk and tibia inclination were manipulated. The average hip/knee extensor moment ratio (HKR) was calculated during the lowering (eccentric) phase of each squat condition using inverse dynamics equations. Linear regression evaluated the association between the difference in trunk and tibia inclination at peak knee flexion and the average HKR. Across all squat conditions, the difference between trunk and tibia inclinations explained 70% of the variance in the average HKR (p < 0.001). The squat was knee extensor biased (HKR ≤ 1.0) when the tibia was at least 8 degrees more inclined than the trunk. The results of this study indicate that the relationship between sagittal plane trunk and tibia inclination can be used to estimate the relative demand of the hip and knee extensors. [ABSTRACT FROM AUTHOR]

The barbell back squat is a highly utilised form of squat exercise and is widely used for the development of strength and power in the lower limb. The high-bar back squat (HBBS) and low-bar back squat (LBBS) are two variations of the barbell back squat. A Google Scholar and PubMed search was conducted to find relevant literature comparing these two forms of back squat. A total of 7934 articles were found and subsequently 12 articles were selected for their relevance to the focused purpose of this study. The current available evidence demonstrated the difference in kinematic and kinetic properties of the HBBS and LBBS. The HBBS exhibited more upright posture and produced more torque and muscle activation at the knee. The HBBS may be a better choice for development of an athlete's vertical jump. The LBBS exhibited greater trunk angle and appeared to have a greater engagement of the posterior chain musculature (hamstrings, gluteals, lumbar erectors). The LBBS was also shown to be more efficient at lifting greater loads. Due to the reduced torque and flexion at the knee joint, the LBBS may be a good alternative to the HBBS when the athlete needs to minimise load on the knee complex due to injuries. The HBBS is a more transferrable skill that makes it more appropriate for most field and court athletes. The LBBS is recommended for use when improving maximal lift and posterior chain strength are the primary goals of the athlete, or when the athlete's tolerance to load in the knees is reduced. [ABSTRACT FROM AUTHOR]

Compared to back squat (BSQ), front squat (FSQ) exhibits a smaller anterior trunk tilt to avoid dropping a barbell held in front of the body, which may lead to increase trunk extension and lumbar lordosis. This study aimed to clarify the differences in the lumbar lordosis angle, anterior trunk tilt angle, and muscle activities of the lower limb and trunk between the FSQ and BSQ. Ten healthy men participated in this study. The participants performed parallel and full FSQ and BSQ. The SQ motion was recorded using three-dimensional motioncapture cameras, and divided into four phases. The lumbar lordosis angle, anterior trunk tilt angle, and lower limb and trunk muscles activity were analyzed. Independent t-tests were used to compare the minimum lumbar lordosis angle and maximum anterior trunk tilt angle between the FSQ and BSQ in each SQ depth. Two-way analysis of variances (barbell positions × phases) were used to compare the mean lumbar lordosis angle and each muscle activity in each phase between the FSQ and BSQ in each SQ depth. The lumbar lordosis angle was significantly larger during FSQ than during BSQ at the minimum value and the mean value in each phase, regardless of depths (P < 0.05). There were no significant differences in the maximum anterior trunk tilt angle and muscle activities of the lower limb and trunk between the FSQ and BSQ in both depths (P > 0.05). These results are the basis for proposing an appropriate SQ style using the FSQ and BSQ to prevent low back pain. [ABSTRACT FROM AUTHOR]

The overhead squat has many applications for the strength and conditioning coach. It is an effective way to improve snatch technique, helps to reveal common issues with mobility, and, with proper corrections, can make the coaches job easier. The purpose of this paper is to explain the basic steps of the overhead squat and how to use the exercise within a strength and conditioning program. Success and safety of the snatch exercise requires the ability to achieve the prerequisite positions exhibited during the overhead squat. The instruction and cues for teaching beginners how to overhead squat are included. How to safely and properly "miss" or drop the barbell limits the risk of injury typically related to mobility issues. Common coaching cues and corrections are presented to help the coach become more effective at improving overhead squat technique. Errors in the overhead squat include the heels coming off the floor, the bar sitting to far behind the athlete, shrugged shoulders, and bent elbows. Cues that can encourage proper movement include, "sit back" to help keep the heels down, "stretch the bar" to keep the bar in position, "squeeze your scaps" to avoid shrugged shoulders, and "punch out" to avoid bent elbows and shoulder internal rotation. Overhead squats have been shown to be useful in detecting potential mobility issues in the shoulder complex, trunk, ankles, and as part of the Functional Movement Screen. For the strength coach the overhead squat can be used as an effective instructional sequence for the snatch, as a squat variation used in training programs, or as a mobility assessment. Technique, properly missing, and common errors and cues are outlined in the video. [ABSTRACT FROM AUTHOR]

In resistance training squats are often used to strengthen the muscles of the lower extremities and core muscles. There are two common forms of squats that use a barbell for loading, the back squat and the front squat. The technique and loading of each squat differ markedly. However, the energetic demands on the muscle between the two forms are not well understood. The purpose of this study was to investigate the difference in energy demands between front and back squats by measuring the change in skeletal muscle oxygen saturation (SmO2) through the use of near infrared spectroscopy (NIRS). Methods: Eleven resistance trained individuals, (5 female, 6 male) with an average age of 23.7 ± 1.4, completed 3 sets of 15 repetitions at 70% of their 1-RM weight for both back and front squats. Skeletal muscle oxygen saturation (SmO2) of the vastus lateralis was measured using a wireless NIRS device. Results: The △SmO2 was not significantly different between back and front squats but was different between sets 1-3 (44.76 ± 3.24% vs. 55.19 ± 2.75% vs. 56.30 ± 2.63%), main effect p = 0.0001. The recovery of SmO2 was significantly different between back (42.5 ± 3.4 sec) and front squats (30.9 ± 2.8 sec), main effect p = 0.05. Conclusions: The findings of this study suggest that the energetic demands placed on the vastus lateralis during both front and back squats are similar with a slower recovery of energetics in the back squat. [ABSTRACT FROM AUTHOR]

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, except one group used the barbell hip thrust (HT) (n = 6) and the other the back squat (SQ) (n = 8). Improvements were observed for both groups in hip thrust 3RM (HT = 34.0%, SQ = 23.8%), back squat 3RM (HT = 34.6%, SQ = 31.0%), vertical jump (HT = 5.4%, SQ = 4.9%), broad jump (HT = 10.5%, SQ = 8.1%), ball kicking distance (HT = 13.2%, SQ = 8.1%), and pro-agility (HT = -1.5%, SQ = -1.5%; faster), but not 36.6-m dash (HT = 2.9%, SQ = 1.9%; slower) with no significant between-group differences. These data indicate that both the hip thrust and the squat provide an effective stimulus to improve these sport-specific performance measures. Practitioners should consider these findings in combination with other factors (equipment availability, ability to coach the movement, training goals, injuries, etc.) when selecting exercises. [ABSTRACT FROM AUTHOR]

Background. This study aimed (I) to assess the inter-rater agreement for measuring the mean velocity (MV) of the barbell with the iLOADR app, and (II) to compare the magnitude of the MV and total work of a training session between the iLOADR app and a linear encoder (reference method). Method. Sixteen young healthy individuals (four women and 12 men) were tested in two sessions separated by 48 h. The 10 repetition maximum (RM) load was determined in the first testing session in the half squat exercise. The second testing session consisted of 3 sets of 10 repetitions during the half squat exercise performed against the 10RM load. Both the iLOADR app and a linear encoder were used to calculate the MV and total work of each training set. MV was recorded with the iLOADR app by two independent researchers to evaluate the inter-rater agreement. Results. Trivial differences and nearly perfect correlations were observed between raters for the MV values collected under individual sets (effect size [ES] ≥ 0.02, r -0:987), as well as for the whole training session (ESD0:01, r D0:997). Trivial-small differences and nearly perfect correlations were observed between the iLOADR app and the linear encoder (Chronojump, Barcelona, Spain) forMV(EV ≥0:25, r = 0:903) and total work (ES ≥ 0:05, r = 0:973). Bland-Altman plots did not reveal heteroscedasticity of the errors between the iLOADR app and the linear encoder for MV (r2 D0:010) and total work (r2 <0:001). Conclusions. iLOADR is a valid smartphone appwhich can provide real-time feedback of the MV and total work completed in a set of multiple repetitions in the half squat exercise. [ABSTRACT FROM AUTHOR]

Weightlifters compete in the snatch, clean and jerk, and total (snatch + clean and jerk). Commonly used assistance exercises for training weightlifters are front barbell squats and back barbell squats. The purpose of this study was to determine relationships between the front barbell squats and back barbell squats one repetition maximum (1 RM) and the snatch, clean and jerk, and total 1 RM. Senior male competitive weightlifters (n = 72) served as subjects in the survey. Significant correlations were found between front barbell squats and snatch, clean and jerk, or total 1 RM (r 2 = 0.85, 0.88, and 0.87 respectively) and between back barbell squats and snatch, clean and jerk, or total 1 RM (r 2 = 0.83, 0.84, and 0.83 respectively). Regression analyses indicate that 1 RM in the snatch, clean and jerk, and total are linearly related to the 1 RM in the front barbell squats and back barbell squats. Superior lifters appeared to be more efficient in using their back barbell squats strength during weightlifting compared to lower level lifters. [ABSTRACT FROM AUTHOR]

Summary Aims The aim of the study was to assess mechanical muscle capacities and profiles of well-trained soccer goalkeepers playing at a national amateur level. Methods Eleven goalkeepers (from 4th French division) performed vertical jump tests and series of loaded half squat and bench throw tests to assess lower and upper limbs force-velocity profiles, respectively. Force, velocity and power produced during each exercise were determined using a guided barbell. Maximal theoretical velocity and maximal theoretical force were determined from the force-velocity profiles. Slopes of those profiles were also calculated. Results Vertical jump performances were 38.5 ± 4.5 cm for the squat jump and 41.6 ± 5.5 cm for the countermovement jump. Lower limbs stiffness was 304.2 ± 55.1 N.m−1.kg−1. Lower limbs force-velocity profile was described by a slope of −11.5 ± 4.0 N.s.m−1.kg−1, with maximal theoretical force and velocity reaching 34.3 ± 5.9 N.kg−1 and 3.2 ± 0.2 m.s−1, respectively. Upper limbs muscular profile was described by a slope of −3.7 ± 1.1 N.s.m−1.kg−1, with maximal theoretical force and velocity of 13.6 ± 3.7 N.kg−1 and 3.7 ± 0.6 m.s−1, respectively. These values reveal that goalkeepers' muscles profiles are oriented towards velocity. Conclusion This suggests that whatever the goalkeepers' level, specific and conditioning trainings should mainly focus on velocity to optimize the performance of this specific soccer player. [ABSTRACT FROM AUTHOR]

Objectives: The velocity of a barbell can provide important insights on the performance of athletes during strength training. The aim of this work was to assess the validity and reliably of four simple measurement devices that were compared to 3D motion capture measurements during squatting. Nine participants were assessed when performing 2 × 5 traditional squats with a weight of 70% of the 1 repetition maximum and ballistic squats with a weight of 25 kg. Simultaneously, data was recorded from three linear position transducers (T-FORCE, Tendo Power and GymAware), an accelerometer based system (Myotest) and a 3D motion capture system (Vicon) as the Gold Standard. Correlations between the simple measurement devices and 3D motion capture of the mean and the maximal velocity of the barbell, as well as the time to maximal velocity, were calculated. Results: The correlations during traditional squats were significant and very high (r = 0.932, 0.990, p < 0.01) and significant and moderate to high (r = 0.552, 0.860, p < 0.01). The Myotest could only be used during the ballistic squats and was less accurate. All the linear position transducers were able to assess squat performance, particularly during traditional squats and especially in terms of mean velocity and time to maximal velocity. [ABSTRACT FROM AUTHOR]

The purpose of this study was to analysis muscles activation of lower back (erector spinal), L1 Para-spinal and L5 Para-spinal muscles while performing two types of squats, i.e. Barbell and Smith Machine Squats. Ten male weight lifters (21.6 ± 2.22 years) selected for the study, they performed one repetition of four different squats. The maximum voluntary contraction (MVC) was recorded with the help of biograph infinity software (EMG). Surface ElectroMyoGraphy (SEMG) was used for measuring muscle electrical activity that occurs during muscle contraction. The eight different squats were barbell front full squat (BFFS), barbell front half squat (BFHS), barbell back full squat (BBFS), barbell back half squat (BBHS), smith machine front full squat (SMFFS), smith machine front half squat (SMFHS), smith machine back full squat (SMBFS) and smith machine back half squat (SMBHS). Although no statistical differences were found in comparing the two types of squats, the muscles activation in smith machine squat is slightly higher in all the eight exercises. Hence, generates slightly more stress in the lower back muscles as compare to the barbell squat. [ABSTRACT FROM AUTHOR]

The purpose of the study was to compare the kinematics of the barbell back squat between two footwear conditions and to evaluate the results with respect to recommendations put forth in the National Strength and Conditioning Association position statement for proper squat technique. Twenty-five subjects with 5 - 7 years of resistance training experience participated. Selected kinematics were measured during a 60% of 1RM barbell back squat in both barefoot and athletic shoe conditions. Paired-samples T tests were performed to compare the two footwear conditions. Significant differences were found in trunk (50.72±8.27 vs. 46.97±9.87), thigh (20.94±10.19 vs. 24.42±11.11), and shank segment angles (59.47±5.54 vs. 62.75±6.17), and knee joint angles (81.33±13.70 vs. 88.32±15.45) at the peak descent position. Based on the kinematic analysis of the barefoot squat, two kinematic advantages are countered by two disadvantages. Coaches and instructors should acknowledge these results with respect to a performer's capability, and be aware the advantages and disadvantages of barefoot squat from a kinematic perspective. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the asymmetries during fatiguing repetitions and sets of the free-weight barbell back squat exercise. The participants of the study were seventeen healthy trained men and women performed 5 sets of 8 repetitions with 90% 8 repetition maximum (RM) while recording bilateral vertical ground reaction force (GRFv). Result suggests that functional asymmetries are present in healthy people during the squat exercise and remain consistently low.

The article presents the results of a study which compared the use of two barbell exercises, the hang clean and squat, in terms of their potential to affect the countermovement vertical jump performance of female college athletes. An overview of related previous research is provided, along with details of the experimental protocol.

The article presents the results of a study which investigated the question of whether left or right lateral dominance is detectable through the kinematics of a barbell, in the context of the squat exercise. An overview of related previous research is provided, along with details of the experimental protocol. Barbell movement was not found to correlate significantly with side dominance as measured by ground reaction force.

The article presents a study which examined the acute effects of elastic bands during free-weight barbell back squat exercises, focusing on power, velocity, and force production. Information on the measurement of power, velocity, and force in test subjects is reviewed. Results suggest that the rate of force development may benefit from the use of elastic bands during squats.

The article presents the results of a study which investigated the impact of a whole-body vibration (WBV) exercise platform on the performance of squats both with and without a barbell. Details of the experimental protocol are provided. It was found that WBV increased the electromyographic activation of the leg muscles.

The article presents the results of a study which investigated the effect of slow, medium or fast lifting cadences when performing the barbell squat exercise. Details of the experimental protocol are presented, which included measuring ground reaction force and calculating inertia effects. It was found that the acceleration of body mass was more significant than the acceleration of the barbell.

The article presents the results of a study which investigated the impact of a weight training exercise called a half squat on teenage male soccer players. The experimental protocol included a cycling force-velocity test, jump tests, and a kinematics analysis. It was found that a program of barbell squats improved the strength and power of the soccer players.

The article presents the results of a study which investigated the effect of increasing weight on subjects' mental models of correct technique when lifting weights. Details of the experimental protocol, which involved squatting with barbells, and assembling a small wooden model to represent the movement, are provided. It was found that increased weight led to increased understanding of correct technique.