Partiels en Position Étirée (Lengthened Partials) vs Amplitude Complète

The study compared changes in strength and regional muscle hypertrophy between different ranges of motion (ROM) in the knee extension exercise. Forty-five untrained women were randomized to either a control group or to perform the exercise in one of the following 4 groups (0°=extended knee): Full ROM (FULLROM: 100°-30° of knee flexion); Initial Partial ROM (INITIALROM: 100°-65°); Final Partial ROM (FINALROM: 65°-30°); Varied ROM (VARROM: daily alternation between the ROM of INITIALROM and FINALROM). Pre- and post-training assessments included one repetition maximum (1RM) testing in the ROM corresponding to the in…

The biarticular triceps brachii long head (TBLong) is lengthened more in the overhead than neutral arm position. We compared triceps brachii hypertrophy after elbow extension training performed in the overhead vs. neutral arm position. Using a cable machine, 21 adults conducted elbow extensions (90-0°) with one arm in the overhead (Overhead-Arm) and the other arm in the neutral (Neutral-Arm) position at 70% one-repetition maximum (1RM), 10 reps/set, 5 sets/session, 2 sessions/week for 12 weeks. Training load was gradually increased (+5% 1RM/session) when the preceding session was completed without repetition fail…

Kassiano, W, Costa, B, Kunevaliki, G, Soares, D, Zacarias, G, Manske, I, Takaki, Y, Ruggiero, MF, Stavinski, N, Francsuel, J, Tricoli, I, Carneiro, MAS, and Cyrino, ES. Greater gastrocnemius muscle hypertrophy after partial range of motion training performed at long muscle lengths. J Strength Cond Res 37(9): 1746-1753, 2023-Whether there is an optimal range of motion (ROM) to induce muscle hypertrophy remains elusive, especially for gastrocnemius. This study aimed to compare the changes in gastrocnemius muscle thickness between calf raise exercise performed with full ROM (FULL ROM ), partial ROM performed in the …

PURPOSE: We investigated the effects of seated versus prone leg curl training on hamstrings muscle hypertrophy and susceptibility to eccentric exercise-induced muscle damage. METHODS: Part 1: Twenty healthy adults conducted seated leg curl training with one leg (Seated-Leg) and prone with the other (Prone-Leg), at 70% one-repetition maximum (1RM), 10 repetitions per set, 5 sets per session, 2 sessions per week for 12 wk. Magnetic resonance imaging (MRI)-measured muscle volume of the individual and whole hamstrings was assessed pre- and posttraining. Part 2: Nineteen participants from part 1 and another 12 untrain…

Regimented resistance training (RT) has been shown to promote increases in muscle size. When engaging in RT, practitioners often emphasize the importance of appropriate exercise technique, especially when trying to maximize training adaptations (e.g., hypertrophy). This narrative review aims to synthesize existing evidence on what constitutes proper RT exercise technique for maximizing muscle hypertrophy, focusing on variables such as exercise-specific kinematics, contraction type, repetition tempo, and range of motion (ROM). We recommend that when trying to maximize hypertrophy, one should employ a ROM that emph…

Goto, M, Chikako, M, Hirayama, T, Terada, S, Nirengi, S, Kurosawa, Y, Nagano, A, and Hamaoka, T. Partial range of motion exercise is effective for facilitating muscle hypertrophy and function through sustained intramuscular hypoxia in young trained men. J Strength Cond Res 33(5): 1286-1294, 2019-The acute response to and long-term effects of partial range of motion exercise (PRE) and full range of motion exercise (FRE) of elbow extensors were compared in young trained men. The PRE was expected to increase the intramuscular hypoxic environment, which was theorized to enhance muscular hypertrophy. Forty-four resist…

The aim of the present study was to analyse the role of exercises' resistance profile in regional hypertrophy. Thirty-eight healthy women completed a 9-week resistance training program consisting of either 4 sets of 12 repetitions to volitional failure of inclined bicep curls (INC group) or preacher curls (PREA group), three times per week. Pre- and post-intervention muscle thickness was measured using B-mode ultrasound imaging with a linear-array transducer. Scan acquisition sites were determined by measuring 50%, 60% and 70% of the distance between the posterior crest of the acromion and the olecranon. Statisti…

Muscle hypertrophy is often a desired goal of resistance training, and strategies that extend training beyond momentary failure may enhance muscular adaptations. Thus, the objective of this study was to assess whether performing additional past-failure partial repetitions beyond momentary failure increased muscle hypertrophy. A total of 23 untrained men completed a 10-week within-participant intervention study. This study comprised two weekly resistance training sessions of four sets of standing Smith machine calf raises. One limb was randomly allocated to the control condition performing sets to momentary failur…

Manipulating joint range of motion during squat training may have differential effects on adaptations to strength training with implications for sports and rehabilitation. Consequently, the purpose of this study was to compare the effects of squat training with a short vs. a long range of motion. Male students (n = 17) were randomly assigned to 12 weeks of progressive squat training (repetition matched, repetition maximum sets) performed as either a) deep squat (0-120° of knee flexion); n = 8 (DS) or (b) shallow squat (0-60 of knee flexion); n = 9 (SS). Strength (1 RM and isometric strength), jump performance, mu…

The purpose of this investigation was to compare partial range-of-motion vs. full range-of-motion upper-body resistance training on strength and muscle thickness (MT) in young men. Volunteers were randomly assigned to 3 groups: (a) full range of motion (FULL; n = 15), (b) partial range of motion (PART; n = 15), or (c) control (CON; n = 10). The subjects trained 2 d · wk(-1) for 10 weeks in a periodized program. Primary outcome measures included elbow flexion maximal strength measured by 1 repetition maximum (1RM) and elbow flexors MT measured by ultrasound. The results indicated that elbow flexion 1RM significant…

Background: The triceps surae muscle plays important roles in fundamental human movements. However, this muscle is relatively unresponsive to resistance training (difficult to hypertrophy) but prone to atrophy with inactivity compared with other muscles. Thus, identifying an effective training modality for the triceps surae is warranted. This study compared triceps surae muscle hypertrophy after standing/knee-extended versus seated/knee-flexed plantarflexion (calf-raise) training, where the gastrocnemius is lengthened and shortened, respectively. Methods: Fourteen untrained adults conducted calf-raise training wi…

OBJECTIVE: The effects of ROM manipulation on muscle strength and hypertrophy response remain understudied in long-term interventions. Thus, we compared the changes in strength and regional muscle hypertrophy after training in protocols with different ranges of motion (ROM) in the seated dumbbell preacher curl exercise using a within-participant experimental design. DESIGN AND METHODS: Nineteen young women had one arm randomly assigned to train in the initial ROM (INITIALROM: 0°-68°; 0° = extended elbow) while the contralateral arm trained in the final ROM (FINALROM: 68°-135°), three times per week over an eight-…

We tested whether explosive resistance training with partial range of motion (ROM) would be as effective as full ROM training using a noninferiority trial design. Fifteen subjects with strength training experience took part in an explosive-concentric only-leg press training program, three times per week for 10 weeks. One leg was randomly assigned to exercise with partial ROM (ie, 9º) and the other leg to full ROM. Before and after training, we assessed leg press performance, isokinetic concentric and isometric knee extension torque, and vastus lateralis muscle architecture. Overall, both training modalities incre…

Front, full, and parallel squats are some of the most popular squat variations. The purpose of this investigation was to compare mean and peak electromyography (EMG) amplitude of the upper gluteus maximus, lower gluteus maximus, biceps femoris, and vastus lateralis of front, full, and parallel squats. Thirteen healthy women (age = 28.9 ± 5.1 y; height = 164 ± 6.3 cm; body mass = 58.2 ± 6.4 kg) performed 10 repetitions of their estimated 10-repetition maximum of each respective variation. There were no statistical (P ≤ .05) differences between full, front, and parallel squats in any of the tested muscles. Given th…

The impact of using different resistance training (RT) kinematics, which therefore alters RT mechanics, and their subsequent effect on adaptations remain largely unreported. The aim of this study was to identify the differences to training at a longer (LR) compared with a shorter (SR) range of motion (ROM) and the time course of any changes during detraining. Recreationally active participants in LR (aged 19 ± 2.6 years; n = 8) and SR (aged 19 ± 3.4 years; n = 8) groups undertook 8 weeks of RT and 4 weeks of detraining. Muscle size, architecture, subcutaneous fat, and strength were measured at weeks 0, 8, 10, and…

PURPOSE: Acute high-intensity unaccustomed eccentric exercise performed by naive subjects is accompanied by disturbances in muscle damage biomarkers. The aim of the study was to investigate whether a causal relationship indeed exists between eccentric exercise and muscle damage. METHODS: Twenty-four men randomly assigned into a concentric only or an eccentric-only training group and performed 10 weeks of isokinetic resistance exercise (one session/week of 75 maximal knee extensors actions). Physiological markers of muscle function and damage (i.e., range of motion, delayed onset muscle soreness, isometric, concen…

The study aimed to compare the effect of performing the same or different exercises for a muscle group on resistance training (RT) sessions on muscle hypertrophy at different sites along muscle length. Twenty-two detrained men (23.3±4.1 years) were randomly allocated to the following groups: a group that performed the same exercises in all training sessions (N-VAR=11) or one that varied the exercises for the same muscle groups (VAR=11). All were submitted to 3 weekly sessions for nine weeks. Muscle thickness was assessed at the proximal, middle, and distal sites of the lateral and anterior thigh, elbow flexors, a…

INTRODUCTION: Modulation of muscle characteristics was attempted through altering muscle stretch during resistance training. We hypothesized that stretch would enhance muscle responses. METHODS: Participants trained for 8 weeks, loading the quadriceps in a shortened (SL, 0-50° knee flexion; n=10) or lengthened (LL, 40-90°; n=11) position, followed by 4 weeks of detraining. Controls (CON; n=10) were untrained. Quadriceps strength, vastus lateralis architecture, anatomical cross-sectional area (aCSA), and serum insulin-like growth factor-1 (IGF-1) were measured at weeks 0, 8, 10, and 12. RESULTS: Increases in fasci…

The ability to perform aerobic or anaerobic exercise varies widely among individuals, partially depending on their muscle-fiber composition. Variability in the proportion of skeletal-muscle fiber types may also explain marked differences in aspects of certain chronic disease states including obesity, insulin resistance, and hypertension. In untrained individuals, the proportion of slow-twitch (Type I) fibers in the vastus lateralis muscle is typically around 50% (range 5-90%), and it is unusual for them to undergo conversion to fast-twitch fibers. It has been suggested that the genetic component for the observed …

PURPOSE: Resistance training using different ranges of motion may produce varying effects on musclular adaptations. The purpose of this study was to compare the effects of lengthened partial repetitions (LPs) vs. full range of motion (ROM) resistance training (RT) on muscular adaptations. METHODS: In this within-participant study, thirty healthy, resistance-trained participants had their upper extremities randomly assigned to either a lengthened partial or full ROM condition; all other training variables were equivalent between limbs. The RT intervention was an 8-week program targeting upper-body musculature. Tra…

BACKGROUND: The regional hypertrophy response of elbow flexor muscles was compared after unilateral elbow flexion training in extended versus flexed shoulder position under vascular occlusion, which can induce muscle hypertrophy in the absence of muscle damage-induced edema/swelling. HYPOTHESIS: Hypertrophy of elbow flexor muscles would be greater in extended compared with flexed shoulder position. STUDY DESIGN: Randomized within-subject trial. LEVEL OF EVIDENCE: Level 2. METHODS: A total of 21 resistance-trained men (age, 25 ± 5 years; height, 1.78 ± 0.07 m; weight, 79.3 ± 13.1 kg) performed unilateral elbow fle…

INTRODUCTION: The hamstring muscles play a crucial role in sprint running but are also highly susceptible to strain injuries, particularly within the biceps femoris long head (BFlh). This study compared the adaptations in muscle size and strength of the knee flexors, as well as BFlh muscle and aponeurosis size, after two eccentrically focused knee flexion training regimes: Nordic hamstring training (NHT) vs lengthened state eccentric training (LSET, isoinertial weight stack resistance in an accentuated hip-flexed position) vs habitual activity (no training controls: CON). METHODS: Forty-two healthy young males co…

Isometric training is used in the rehabilitation and physical preparation of athletes, special populations, and the general public. However, little consensus exists regarding training guidelines for a variety of desired outcomes. Understanding the adaptive response to specific loading parameters would be of benefit to practitioners. The objective of this systematic review, therefore, was to detail the medium- to long-term adaptations of different types of isometric training on morphological, neurological, and performance variables. Exploration of the relevant subject matter was performed through MEDLINE, PubMed, …

OBJECTIVE: To demonstrate the response to a proprioceptive training model during a 1-week rehabilitation regime. The techniques were demonstrated on a college-aged female basketball player who had injured her anterior cruciate ligament (ACL) several weeks earlier. The athlete was tested, trained, and then retested during her semester break. BACKGROUND: The ACL injury has become a fairly common occurrence in the world of athletics. Knowing this, the athletic trainer is constantly searching for ways to improve the rehabilitative process. New research demonstrates that rehabilitation should be based on proprioceptio…

Muscular strength and hypertrophy following resistance training may be obtained in different degrees depending on the approach performed. This study was designed to compare the responses of the biceps brachii to two preacher curl exercises, one performed on a cable-pulley system (CAB; in which a greater torque was applied during the exercise when elbows were flexed and biceps shortened) and one performed with a barbell (BAR; in which greater torque was applied when the elbows were extended and biceps stretched). Thirty-five young adults (CAB: 13 men, 5 women; BAR: 12 men, 5 women; age = 24 ± 5 years) performed a …

This study was undertaken to investigate physiological adaptation with two endurance-training periods differing in intensity distribution. In a randomized crossover fashion, separated by 4 wk of detraining, 12 male cyclists completed two 6-wk training periods: 1) a polarized model [6.4 (±1.4 SD) h/wk; 80%, 0%, and 20% of training time in low-, moderate-, and high-intensity zones, respectively]; and 2) a threshold model [7.5 (±2.0 SD) h/wk; 57%, 43%, and 0% training-intensity distribution]. Before and after each training period, following 2 days of diet and exercise control, fasted skeletal muscle biopsies were ob…

INTRODUCTION: This study compared the effects of dumbbell versus cable lateral raises on lateral deltoid muscle thickness (MT) in resistance-trained men and women, with shoulder adduction/abduction range of motion standardised and matched between conditions. METHODS: Twenty-four participants completed an eightweek intervention comprising two weekly resistance training sessions of five sets of lateral raises completed to momentary failure. The study employed a within-participant design with each participant's arms randomly allocated to the cable or dumbbell lateral raise. MT of the proximal and distal lateral delt…

BACKGROUND: Although it is known that resistance training can be as effective as stretch training to increase joint range of motion, to date no comprehensive meta-analysis has investigated the effects of resistance training on range of motion with all its potential affecting variables. OBJECTIVE: The objective of this systematic review with meta-analysis was to evaluate the effect of chronic resistance training on range of motion compared either to a control condition or stretch training or to a combination of resistance training and stretch training to stretch training, while assessing moderating variables. DESI…

Background: In animal studies long-term stretching interventions up to several hours per day have shown large increases in muscle mass as well as maximal strength. The aim of this study was to investigate the effects of a long-term stretching on maximal strength, muscle cross sectional area (MCSA) and range of motion (ROM) in humans. Methods: 52 subjects were divided into an Intervention group (IG, n = 27) and a control group (CG, n = 25). IG stretched the plantar flexors for one hour per day for six weeks using an orthosis. Stretching was performed on one leg only to investigate the contralateral force transfer.…

(1) Background: Stretching is known to improve range of motion (ROM), and evidence has suggested that strength training (ST) is effective too. However, it is unclear whether its efficacy is comparable to stretching. The goal was to systematically review and meta-analyze randomized controlled trials (RCTs) assessing the effects of ST and stretching on ROM (INPLASY 10.37766/inplasy2020.9.0098). (2) Methods: Cochrane Library, EBSCO, PubMed, Scielo, Scopus, and Web of Science were consulted in October 2020 and updated in March 2021, followed by search within reference lists and expert suggestions (no constraints on l…

Recently, there has been a shift from static stretching (SS) or proprioceptive neuromuscular facilitation (PNF) stretching within a warm-up to a greater emphasis on dynamic stretching (DS). The objective of this review was to compare the effects of SS, DS, and PNF on performance, range of motion (ROM), and injury prevention. The data indicated that SS- (-3.7%), DS- (+1.3%), and PNF- (-4.4%) induced performance changes were small to moderate with testing performed immediately after stretching, possibly because of reduced muscle activation after SS and PNF. A dose-response relationship illustrated greater performan…

Resistance to stretch, electromyographic (EMG) response to stretch, stretch discomfort and maximum range of motion (ROM) were measured during passive hamstring stretches performed in the slump test position (neural tension stretch) and in the upright position (neutral stretch) in eight healthy subjects. Stretches were performed on an isokinetic dynamometer at 5°/s with the test thigh flexed 40° above the horizontal, and the seat back at 90° to the horizontal. Surface EMG signals were recorded from the medial and lateral hamstrings during stretches. Knees were passively extended to maximum stretch tolerance with t…

An objective of a warm-up prior to an athletic event is to optimize performance. Warm-ups are typically composed of a submaximal aerobic activity, stretching and a sport-specific activity. The stretching portion traditionally incorporated static stretching. However, there are a myriad of studies demonstrating static stretch-induced performance impairments. More recently, there are a substantial number of articles with no detrimental effects associated with prior static stretching. The lack of impairment may be related to a number of factors. These include static stretching that is of short duration (<90 s total) …

The hippocampus shrinks in late adulthood, leading to impaired memory and increased risk for dementia. Hippocampal and medial temporal lobe volumes are larger in higher-fit adults, and physical activity training increases hippocampal perfusion, but the extent to which aerobic exercise training can modify hippocampal volume in late adulthood remains unknown. Here we show, in a randomized controlled trial with 120 older adults, that aerobic exercise training increases the size of the anterior hippocampus, leading to improvements in spatial memory. Exercise training increased hippocampal volume by 2%, effectively re…

Wearing high heels (HH) places the calf muscle-tendon unit (MTU) in a shortened position. As muscles and tendons are highly malleable tissues, chronic use of HH might induce structural and functional changes in the calf MTU. To test this hypothesis, 11 women regularly wearing HH and a control group of 9 women were recruited. Gastrocnemius medialis (GM) fascicle length, pennation angle and physiological cross-sectional area (PCSA), the Achilles' tendon (AT) length, cross-sectional area (CSA) and mechanical properties, and the plantarflexion torque-angle and torque-velocity relationships were assessed in both group…

Despite its increasing use in experimental and clinical settings, the cellular and molecular mechanisms underlying transcranial direct current stimulation (tDCS) remain unknown. Anodal tDCS applied to the human motor cortex (M1) improves motor skill learning. Here, we demonstrate in mouse M1 slices that DCS induces a long-lasting synaptic potentiation (DCS-LTP), which is polarity specific, NMDA receptor dependent, and requires coupling of DCS with repetitive low-frequency synaptic activation (LFS). Combined DCS and LFS enhance BDNF-secretion and TrkB activation, and DCS-LTP is absent in BDNF and TrkB mutant mice,…

We evaluated the effects of concurrent strength and aerobic endurance training on muscle strength and endurance, body composition, and flexibility in female college athletes and compared two concurrent exercise (CE) protocols. Twenty-eight women (mean age, 19.6 years) were divided into two matched groups and evaluated before and after a vigorous, 11-week, 3-days per week CE training program. One group did serial CE consisting of a warm-up, resistance exercises at low heart rate (HR), aerobics, and a range of motion cool down. The other group did integrated CE consisting of aerobics, the same resistance exercises …

Constant cerebral blood flow (CBF) is vital to human survival. Originally thought to receive steady blood flow, the brain has shown to experience increases in blood flow during exercise. Although increases have not consistently been documented, the overwhelming evidence supporting an increase may be a result of an increase in brain metabolism. While an increase in metabolism may be the underlying causative factor for the increase in CBF during exercise, there are many modulating variables. Arterial blood gas tensions, most specifically the partial pressure of carbon dioxide, strongly regulate CBF by affecting cer…

BACKGROUND AND PURPOSE: Frequency and duration of static stretching have not been extensively examined. Additionally, the effect of multiple stretches per day has not been evaluated. The purpose of this study was to determine the optimal time and frequency of static stretching to increase flexibility of the hamstring muscles, as measured by knee extension range of motion (ROM). SUBJECTS: Ninety-three subjects (61 men, 32 women) ranging in age from 21 to 39 years and who had limited hamstring muscle flexibility were randomly assigned to one of five groups. The four stretching groups stretched 5 days per week for 6…

Because of the inability of strength tests to accurately discriminate between low back pain patients and healthy subjects, a multifactorial evaluation of low back pain patients is warranted. It is postulated that measurements of endurance, kinematics, postural stability, and coordination, in addition to strength, are necessary to fully document the patients' functional capabilities. This research study was conducted in order to understand the effects of fatigue on the above factors. Twelve healthy male subjects performed a repetitive lifting test in which a submaximal load was lifted at a maximal rate. Knee, hip,…

We hypothesized that the moment arms of muscles crossing the elbow vary substantially with forearm and elbow position and that these variations could be represented using a three-dimensional computer model. Flexion/extension and pronation/supination moment arms of the brachioradialis, biceps, brachialis, pronator teres, and triceps were calculated from measurements of tendon displacement and joint angle in two anatomic specimens and were estimated using a computer model of the elbow joint. The anatomical measurements revealed that the flexion/extension moment arms varied by at least 30% over a 95 degrees range of…

This study investigated the effect of knee flexion range of motion (ROM) during the leg press exercise on quadriceps femoris muscle hypertrophy in resistance-trained individuals. Twenty-three participants (training age: 7.2 ± 3.5 years) completed a within-participant design, performing four sets of unilateral leg presses to momentary failure twice weekly for 8 weeks. In one leg, the knee flexion range of motion (ROM) was fixed at approximately 5-100°, while for the other leg, participants used their maximum individualized ROM (5-154 ± 7.8°). Quadriceps muscle thickness was assessed via B-mode ultrasonography in t…

This study compared calf training with initial partial repetitions versus full range-of-motion (ROM) repetitions followed by past-failure partials on gastrocnemius hypertrophy. Twenty-three participants (men: n = 16 and women: n = 7) performed four sets of unilateral Smith machine calf raises to momentary failure twice a week for 8 weeks. One leg was trained using initial partials to their individualized maximum dorsiflexion ROM. The contralateral leg was trained with a full ROM and continued with past-failure partials after failure in peak plantarflexion. Medial gastrocnemius muscle thickness was measured with u…

Stretch training is widely used in a variety of fitness-related capacities such as increasing joint range of motion, preventing contractures and alleviating injuries. Moreover, some researches indicate that stretch training may induce muscle hypertrophy; however, studies on the topic have been primarily relegated to animal and in vitro models. The purpose of this brief review was to evaluate whether stretch training is a viable strategy to induce muscle hypertrophy in humans. An extensive literature search was performed using PubMed/MEDLINE, SciELO and Scopus databases, using terms related to stretching and muscl…

This study examined the time course of recovery following resistance exercise sessions in the back squat, bench press, and deadlift. Twelve well-trained males (age: 24.5 ± 3.8 years, body mass: 84.01 ± 15.44 kg, training age: 7.1 ± 4.2 years) performed 4 sets to failure at 80% of a 1-repetition maximum (1RM) on the squat, bench press, and deadlift in successive weeks. The bench press was always performed in week 2 with the squat and deadlift order counterbalanced between weeks 1 and 3. Indirect muscle damage and performance fatigue was assessed immediately before and after exercise and at 24 h, 48 h, 72 h, and 96…

PURPOSE: The purpose of this study was to determine the effect of a 15-week partial range of motion (ROM) resistance training program on the vastus lateralis (VL) architecture and mechanical properties, when the time under tension (TUT) was equalized. METHODS: Nineteen untrained male subjects were randomly assigned to a control (Control; n = 8) or training (TG; n = 11) group. In the TG, the dominant and nondominant legs were randomly selected to be trained with a full ROM (FULL) or a partial ROM (PART) in an isokinetic dynamometer. Training volume was equalized based on the TUT by manipulating sets and repetition…

The purpose of the study was to remove the influence of an external load and determine if muscle growth can be elicited by maximally contracting through a full range of motion. In addition, the acute physiologic and perceptual responses to each stimulus were also investigated. Thirteen participants completed 18 sessions of unilateral elbow flexion exercise. Each arm was designated to either NO LOAD or HIGH LOAD condition (70% one repetition maximum). For the NO LOAD condition, participants repeatedly contracted as hard as they could through a full range of motion without the use of an external load. Our results s…

Squatting is a common strength training exercise used for rehabilitation, fitness training, and in preparation for competition. Knowledge about the loading and the motion of the back during the squat exercise is crucial to avoid overuse or injury. The aim of this study was the measurement and comparison of the kinematics of the lower leg, trunk, and spine during unrestricted and restricted (knees are not allowed beyond toes) squats. A total of 30 subjects performed unrestricted and restricted barbell squats with an extra load of 0, 25, and 50% bodyweight. Motion was tracked using a 12-camera Vicon system. A newly…

STUDY DESIGN: Randomized controlled trial. OBJECTIVE: To compare the effects of full range of motion (ROM) and limited ROM isolated lumbar extension exercise upon full ROM lumbar extension strength, ROM, perceived pain, and disability. SUMMARY OF BACKGROUND DATA: Limited ROM is common in chronic low back pain as is lumbar extensor deconditioning. Limited ROM exercise is a common prescription but is yet to be empirically tested. METHODS: Males (n = 21) and females (n = 17) with nonspecific chronic low back pain were initially recruited. Participants were randomized to either a full ROM (FullROM) or limited ROM (Li…

The purpose of this study was to measure the relative contributions of 4 hip and thigh muscles while performing squats at 3 depths. Ten experienced lifters performed randomized trials of squats at partial, parallel, and full depths, using 100-125% of body weight as resistance. Electromyographic (EMG) surface electrodes were placed on the vastus medialis (VMO), the vastus lateralis, (VL), the biceps femoris (BF), and the gluteus maximus (GM). EMG data were quantified by integration and expressed as a percentage of the total electrical activity of the 4 muscles. Analysis of variance (ANOVA) and Tukey post hoc tests…

STUDY DESIGN: Repeated measures analysis of joint angle effects on hip and knee muscle electromyographic (EMG) activity. OBJECTIVES: To simultaneously determine angle-dependent changes in maximal voluntary isometric contraction (MVIC) torque and EMG activity during hip extension and knee flexion. BACKGROUND: Procedures for normalizing EMG data and for determining torque-angle relationships for various joint motions both entail asking subjects to exert an MVIC. The implicit assumption in these paradigms is that magnitude of the EMG response is at a constant, maximum level so that observed angle-dependent variation…

Biopsies (biceps) were examined in 8 bodybuilders across a typical arm-curl training session (80% 1-RM). [PCr] and [glycogen] decreased 62 and 12% after 1 set (n = 4), and 50 and 24% after 3 sets (n = 4). [Lactate] was 91 and 118 mmol &times kg-1, respectively, after 1 and 3 sets. Fatigue was probably partially caused by decreased [PCr] and increased [H+] (first set) and by decreased [H+] in subsequent sets.

Background: The triceps surae muscle plays important roles in fundamental human movements. However, this muscle is relatively unresponsive to resistance training (difficult to hypertrophy) but prone to atrophy with inactivity compared with other muscles. Thus, identifying an effective training modality for the triceps surae is warranted. This study compared triceps surae muscle hypertrophy after standing/knee-extended versus seated/knee-flexed plantarflexion (calf-raise) training, where the gastrocnemius is lengthened and shortened, respectively. Methods: Fourteen untrained adults conducted calf-raise training wi…

The aim of this study was to investigate (1) whether factors related to endurance performance are associated with physiological resilience in recreational-to-competitive runners, and (2) differences between recreational and competitive runners in physiological resilience. During three test days, 33 runners (15 competitive and 18 recreational) were tested for their peak fat oxidation, maximal blood lactate concentration (Lamax) after maximal anaerobic running test (MART), maximal voluntary contraction (MVC) in isometric leg press, maximal oxygen uptake (VO2max), maximal speed of incremental test (sPeak), speeds at…

PURPOSE: This study examined how maximal glycolytic flux, indexed by the peak lactate accumulation rate (vLapeak) from a 15-s sprint, relates to lactate- and gas-exchange derived endurance thresholds at a given V̇O2max in trained cyclists. METHODS: Fifty cyclists (30 men, 20 women) completed two laboratory visits: a ramp test with verification to determine V̇O2max, and on a separate day, a 15-s all-out sprint with repeated post-exercise capillary blood sampling to determine peak lactate accumulation (ΔLa) and derived vLapeak, followed by a 3-min step-increment test with lactate and gas-exchange measurements. RESU…

The time spent above 90% of maximal oxygen uptake ( V ˙ O2max) during high-intensity interval training (HIIT) sessions is intended to be maximized to improve V ˙ O2max. Since uphill running serves as a promising means to increase metabolic cost, we compared even and moderately inclined running in terms of time ≥90% V ˙ O2max and its corresponding physiological surrogates. Seventeen well-trained runners (8 females & 9 males; 25.8 ± 6.8yrs; 1.75 ± 0.08m; 63.2 ± 8.4kg; V ˙ O2max: 63.3 ± 4.2 ml/min/kg) randomly completed both a horizontal (1% incline) and uphill (8% incline) HIIT protocol (4-times 5min, with 90s rest…

Martínez-Cava, A, Hernández-Belmonte, A, Courel-Ibáñez, J, Morán-Navarro, R, González-Badillo, JJ, and Pallarés, JG. Bench press at full range of motion produces greater neuromuscular adaptations than partial executions after prolonged resistance training. J Strength Cond Res 36(1): 10-15, 2022-Training at a particular range of motion (ROM) produces specific neuromuscular adaptations. However, the effects of full and partial ROM in one of the most common upper-limb exercises such as the bench press (BP) remain controversial. In this study, 50 recreationally to highly resistance trained men were randomly assigned …

The coupled motions of tibial internal rotation (T-IR) and ankle dorsiflexion (DF) are necessary for proper lower-limb function. Anecdotally, clinicians have been performing techniques to restore T-IR to improve ankle DF, however, no evidence exists to support their efficacy. Therefore, the two objectives were to: (a) determine the effectiveness of a manual therapy technique for improving T-IR range of motion (ROM) and (b) Examine the relationship between ankle DF and T-IR ROM. Twenty-four participants qualified to participate and were randomly allocated to either the control (n=12) or manual therapy (n=12) group…

KEY POINTS: Brief (5-6 days) adaptation to a low carbohydrate high fat diet in elite athletes increased exercise fat oxidation to rates previously observed with medium (3-4 weeks) or chronic (>12 months) adherence to this diet, with metabolic changes being washed out in a similar time frame. Increased fat utilisation during exercise was associated with a 5-8% increase in oxygen cost at speeds related to Olympic Programme races. Acute restoration of endogenous carbohydrate (CHO) availability (24 h high CHO diet, pre-race CHO) only partially restored substrate utilisation during a race warm-up. Fat oxidation contin…

The purpose of this study was to systematically review the literature as to the effects of performing exercise with a full versus partial range of motion (ROM) during dynamic, longitudinal resistance training (RT) programs on changes in muscle hypertrophy. Based on the available literature, we aimed to draw evidence-based recommendations for RT prescription. Six studies were identified as meeting inclusion criteria: four of these studies involved RT for the lower limbs while the other two focused on the upper extremities. The total combined sample of the studies was n = 135, which comprised 127 men and 8 women. T…

INTRODUCTION: Ageing is associated with an attenuated hypertrophic response to resistance training and periods of training interruptions. Hence, elderly would benefit from the 'muscle memory' effects of resistance training on muscle strength and mass during detraining and retraining. As the underlying mechanisms are not yet clear, this study investigated the role of myonuclei during training, detraining and retraining by using PCM1 labelling in muscle cross-sections of six older men. METHODS: Knee extension strength and power were measured in 30 older men and 10 controls before and after 12 weeks resistance train…

BACKGROUND: The architectural and morphological adaptations of the hamstrings in response to training with different exercises have not been explored. PURPOSE: To evaluate changes in biceps femoris long head (BFLH) fascicle length and hamstring muscle size following 10-weeks of Nordic hamstring exercise (NHE) or hip extension (HE) training. METHODS: 30 recreationally active male athletes (age, 22.0±3.6 years; height, 180.4±7 cm; weight, 80.8±11.1 kg) were allocated to 1 of 3 groups: (1) HE training (n=10), NHE training (n=10), or no training (control, CON) (n=10). BFLH fascicle length was assessed before, during …

The main purpose of this study was to assess the acute effects of small changes in crank length (assumable by competitive cyclists) on metabolic cost and pedalling technique during submaximal cycling. Twelve amateur road cyclists performed three sets of submaximal pedalling (150, 200 and 250 W) at a constant cadence (91.3 ± 0.8 rpm) in a randomised order with three commonly used crank lengths, preferred (172.5-175 mm), +5 mm and -5 mm. Energy cost of pedalling, kinetic and kinematic variables were simultaneously registered. Changes in crank length had no significant effect on heart rate (144 ± 13, 145 ± 12 and 14…

Cold water immersion (CWI) is used by endurance athletes to speed recovery between exercise bouts, but little evidence is available on the effects of CWI on subsequent endurance performance. The purpose of this study was to investigate the effects of CWI following an acute bout of interval training on 5000 m run performance 24 hrs after interval training, perceived muscle soreness (PMS), range of motion (ROM), thigh circumference (TC), and perceived exertion (RPE). Nine endurance-trained males completed 2 trials, each consisting of an interval training session of 8 repetitions of 1200 m at a running pace equal to…

Cells of the osteoblast lineage are increasingly identified as participants in whole-body metabolism by primarily targeting pancreatic insulin secretion or consuming energy. Osteocytes, the most abundant bone cells, secrete a Wnt-signaling inhibitor called sclerostin. Here we examined three mouse models expressing high sclerostin levels, achieved through constitutive or inducible loss of the stimulatory subunit of G-proteins (Gsα in mature osteoblasts and/or osteocytes). These mice showed progressive loss of white adipose tissue (WAT) with tendency toward increased energy expenditure but no changes in glucose or …

A pattern of excessive hip adduction and internal rotation with medial deviation of the knee has been associated with numerous musculo-skeletal dysfunctions. Research into the role that ankle dorsiflexion (DF) range of motion (ROM) play in lower limb kinematics is lacking. The objective of this cross-sectional, observational study was to investigate the relationship between ankle DF ROM, and hip adduction and hip internal rotation during a step-down test with and without heel elevation in a healthy female population. Hip and ankle ROM was measured kinematically using a ten-camera Optitrack motion analysis system.…

Background. Foam rolling has been shown to acutely increase range of motion (ROM) during knee flexion and hip flexion with the experimenter applying an external force, yet no study to date has measured hip extensibility as a result of foam rolling with controlled knee flexion and hip extension moments. The purpose of this study was to investigate the acute effects of foam rolling on hip extension, knee flexion, and rectus femoris length during the modified Thomas test. Methods. Twenty-three healthy participants (male = 7; female = 16; age = 22 ± 3.3 years; height = 170 ± 9.18 cm; mass = 67.7 ± 14.9 kg) performed …

The anabolic effect of resistance training can mitigate muscle loss during contest preparation. In reviewing relevant literature, we recommend a periodized approach be utilized. Block and undulating models show promise. Muscle groups should be trained 2 times weekly or more, although high volume training may benefit from higher frequencies to keep volume at any one session from becoming excessive. Low to high (~3-15) repetitions can be utilized but most repetitions should occur in the 6-12 range using 70-80% of 1 repetition maximum. Roughly 40-70 reps per muscle group per session should be performed, however high…

The use of self myofascial release (SMR) via a foam roller or roller massager is becoming increasingly popular both to aid recovery from exercise and prevent injury. Our objective was to review the literature on SMR and its use for preexercise, recovery, or maintenance. PUBMED, EBSCO (MEDLINE), EMBASE, and CINAHL were searched for variations and synonyms of "self myofascial release" and "foam rolling." Data from nine studies were examined, and overall quality varied based on study protocol, muscle group targeted, and outcomes measured. Despite the heterogeneity of these studies, SMR appears to have a positive eff…

This study investigated biceps brachii distal myotendinous junction (MTJ) displacement during maximal eccentric elbow flexor contractions to test the hypothesis that muscle length change would be smaller (less MTJ displacement) during the second than the first exercise bout. Ten untrained men performed two eccentric exercise bouts (ECC1 and ECC2) with the same arm consisting of 10 sets of six maximal isokinetic (60°/s) eccentric elbow flexor contractions separated by 4 wk. Biceps brachii distal MTJ displacement was assessed using B-mode ultrasonography, and changes in the displacement (muscle length change) from …

The broad immunologic roles of autophagy span innate and adaptive immunity and are often manifested in inflammatory diseases. The immune effects of autophagy partially overlap with its roles in metabolism and cytoplasmic quality control but typically expand further afield to encompass unique immunologic adaptations. One of the best-appreciated manifestations of autophagy is protection against microbial invasion, but this is by no means limited to direct elimination of intracellular pathogens and includes a stratified array of nearly all principal immunologic processes. This Review summarizes the broad immunologic…

The aim of the present investigation was to evaluate the acute effects of foam rolling (FR) and a new form of instrument-assisted soft tissue mobilization (IASTM), Fascial Abrasion Technique ™ (FAT) on hip and knee range of motion in soccer players. Twenty male soccer players randomly allocated into FR and FAT group (n = 10 each). Passive knee flexion and straight leg raise tests were measured before, immediately after and 24 h after intervention (FR or FAT). The FR group applied a 2-min quadriceps and hamstrings rolling, while FAT group received a 2-min application of FAT to the quadriceps and hamstrings muscles…

PURPOSE: To analyse the muscle adaptations induced by two protocols of isometric training performed at different muscle lengths. METHODS: Twenty-eight subjects were divided into three groups: one (K90) performed isometric training of the knee extensors at long muscle lengths (90° of knee flexion) for 8 weeks, and the second group (K50) at short muscle lengths (50°). The subjects of the third group acted as controls. Isokinetic dynamometry was utilized to analyse the net moment-angle relationship and vastus lateralis muscle thickness at three different locations, and pennation angles and fascicle length at 50 % of…

Sleep has numerous important physiological and cognitive functions that may be particularly important to elite athletes. Recent evidence, as well as anecdotal information, suggests that athletes may experience a reduced quality and/or quantity of sleep. Sleep deprivation can have significant effects on athletic performance, especially submaximal, prolonged exercise. Compromised sleep may also influence learning, memory, cognition, pain perception, immunity and inflammation. Furthermore, changes in glucose metabolism and neuroendocrine function as a result of chronic, partial sleep deprivation may result in altera…

BACKGROUND: Limited dorsiflexion range of motion (ROM) has been linked to lower limb injuries. Improving limited ankle ROM may decrease injury rates. Static stretching (SS) is ubiquitously used to improve ROM but can lead to decreases in force and power if performed prior to the activity. Thus, alternatives to improve ROM without performance decrements are needed. OBJECTIVES/PURPOSE: To compare the effects of SS and self massage (SM) with a roller massage of the calf muscles on ankle ROM, maximal voluntary contraction (MVC) force F100 (force produced in the first 100 ms of the MVC), electromyography (EMG of soleu…

The purpose of the study was to determine the effects of static and dynamic stretching protocols within general and activity specific warm-ups. Nine male and ten female subjects were tested under four warm-up conditions including a 1) general aerobic warm-up with static stretching, 2) general aerobic warm-up with dynamic stretching, 3) general and specific warm-up with static stretching and 4) general and specific warm-up with dynamic stretching. Following all conditions, subjects were tested for movement time (kicking movement of leg over 0.5 m distance), countermovement jump height, sit and reach flexibility an…

BACKGROUND: The effect of footwear on the gait of children is poorly understood. This systematic review synthesises the evidence of the biomechanical effects of shoes on children during walking and running. METHODS: Study inclusion criteria were: barefoot and shod conditions; healthy children aged ≤ 16 years; sample size of n > 1. Novelty footwear was excluded. Studies were located by online database-searching, hand-searching and contact with experts. Two authors selected studies and assessed study methodology using the Quality Index. Meta-analysis of continuous variables for homogeneous studies was undertaken us…

Pentadecapeptide BPC 157, composed of 15 amino acids, is a partial sequence of body protection compound (BPC) that is discovered in and isolated from human gastric juice. Experimentally it has been demonstrated to accelerate the healing of many different wounds, including transected rat Achilles tendon. This study was designed to investigate the potential mechanism of BPC 157 to enhance healing of injured tendon. The outgrowth of tendon fibroblasts from tendon explants cultured with or without BPC 157 was examined. Results showed that BPC 157 significantly accelerated the outgrowth of tendon explants. Cell prolif…

This study compared a conventional pull-up and chin-up with a rotational exercise using Perfect·Pullup™ twisting handles. Twenty-one men (24.9 ± 2.4 years) and 4 women (23.5 ± 1 years) volunteered to participate. Electromyographic (EMG) signals were collected with DE-3.1 double-differential surface electrodes at a sampling frequency of 1,000 Hz. The EMG signals were normalized to peak activity in the maximum voluntary isometric contraction (MVIC) trial and expressed as a percentage. Motion analysis data of the elbow were obtained using Vicon Nexus software. One-factor repeated measures analysis of variance examin…