Effect of a gluteal activation warm-up on explosive exercise performance

Acute Effect of Dynamic and Gluteal Resistance Exercise Warm-up Protocols on Jump Landing Mechanics in College-Aged Females

ABSTRACT

Rauseo, ML, Feairheller, DL, LaRoche, DP, and Cook, SB. Acute effect of dynamic and gluteal resistance exercise warm-up protocols on lower-extremity jump landing mechanics in college-aged females. J Strength Cond Res 38(2): 259-265, 2024-Inadequate neuromuscular control of the femur by the gluteal musculature is associated with noncontact and overuse injuries to the knee. Acute bouts of resistance exercises targeting the gluteal musculature can be prescribed as part of a warm-up protocol with the goal of improving subsequent neuromuscular control and performance. The purpose of this study was to determine the effect that a warm-up protocol including moderate-intensity gluteal resistance exercises (GRE) has on single leg jump landing biomechanics. Seventeen healthy, college-aged, recreationally active females (mean ± SD ; age = 21.4 ± 1.9 years; height = 166.9 ± 5.7 cm; body mass = 62.5 ± 7.4 kg) performed 3 single leg hop trials per leg after completing no warm-up (CON), a dynamic warm-up (DWU), and a dynamic warm-up with gluteal resistance exercises (DWU + GRE) across 3 laboratory visits. Lower extremity kinetic and kinematic variables were assessed during single leg hops from the point of initial foot contact to deepest knee flexion. Biomechanical differences between dominant and nondominant limb landings were also assessed. Dominant limb hip internal rotation angle after DWU + GRE (2.03 ± 9.92°) was significantly greater ( p ≤ 0.05) compared with CON (-3.36 ± 7.74°). Peak knee adduction moment (56.8%), peak knee flexion angle (5.7%), and peak knee external rotation angle (17.0%) were significantly greater ( p ≤ 0.017) in the dominant limb, compared with the nondominant limb, across warm-up protocols. The combined DWU + GRE warm-up protocol did not have a substantial impact on landing biomechanics. Clinicians prescribing GRE before activity should not expect significant changes in movement patterns after a single bout.

Post-Activation Performance Enhancement and Motor Imagery Are Efficient to Emphasize the Effects of a Standardized Warm-Up on Sprint-Running Performances

Warm-up routines include various tasks focused on the peripheral contractile properties and nervous motor command. This present study was aimed at investigating the acute effects of different warm-up routines, emphasizing either peripheral (post-activation performance enhancement, PAPE) or central (motor imagery, MI) contributions on sport-specific tasks. Eleven young female athletes took part in this cross-over, randomized, controlled trial. They underwent three experimental sessions composed of a standardized warm-up followed by 10 min of (1) rest (CONTROL), (2) maximal concentric leg press (PAPE), or (3) mental repetitions of sprint tasks (MI). Post-tests consisted of reaction time, arrowhead agility test, 20 m sprint, repeated sprint ability, and NASA-TLX fatigue questionnaire. PAPE and MI significantly enhanced the arrowhead agility test (p < 0.001 and p = 0.012, respectively) and repeated sprint ability (p = 0.002 and p = 0.035, respectively) compared to CONTROL, without any difference between PAPE and MI. The 20 m sprint time was better after PAPE as compared to MI (p = 0.005) and CONTROL (p < 0.001), without any difference between MI and CONTROL. Reaction time and the NASA-TLX questionnaire were not affected by the warm-up modalities (p > 0.05). PAPE was the most efficient to optimize warm-up due to its greater peripheral contribution that would improve muscle contractility. MI specifically improved the imagined tasks mostly by central contribution.

Efficacy of Hip Strengthening on Pain Intensity, Disability, and Strength in Musculoskeletal Conditions of the Trunk and Lower Limbs: A Systematic Review with Meta-Analysis and Grade Recommendations

To investigate the efficacy of hip strengthening on pain, disability, and hip abductor strength in musculoskeletal conditions of the trunk and lower limbs, we searched eight databases for randomized controlled trials up to 8 March 2022 with no date or language restrictions. Random-effect models estimated mean differences (MDs) with 95% confidence intervals (CIs), and the quality of evidence was assessed using the GRADE approach. Very low quality evidence suggested short-term effects (≤3 months) of hip strengthening on pain intensity (MD of 4.1, 95% CI: 2.1 to 6.2; two trials, n = 48 participants) and on hip strength (MD = 3.9 N, 95% CI: 2.8 to 5.1; two trials, n = 48 participants) in patellofemoral pain when compared with no intervention. Uncertain evidence suggested that hip strengthening enhances the short-term effect of the other active interventions on pain intensity and disability in low back pain (MD = -0.6 points, 95% CI: 0.1 to 1.2; five trials, n = 349 participants; MD = 6.2 points, 95% CI: 2.6 to 9.8; six trials, n = 389 participants, respectively). Scarce evidence does not provide reliable evidence of the efficacy of hip strengthening in musculoskeletal conditions of the trunk and lower limbs.

Usefulness of Surface Electromyography Complexity Analyses to Assess the Effects of Warm-Up and Stretching during Maximal and Sub-Maximal Hamstring Contractions: A Cross-Over, Randomized, Single-Blind Trial

This study aimed to apply different complexity-based methods to surface electromyography (EMG) in order to detect neuromuscular changes after realistic warm-up procedures that included stretching exercises. Sixteen volunteers conducted two experimental sessions. They were tested before, after a standardized warm-up, and after a stretching exercise (static or neuromuscular nerve gliding technique). Tests included measurements of the knee flexion torque and EMG of biceps femoris (BF) and semitendinosus (ST) muscles. EMG was analyzed using the root mean square (RMS), sample entropy (SampEn), percentage of recurrence and determinism following a recurrence quantification analysis (%Rec and %Det) and a scaling parameter from a detrended fluctuation analysis. Torque was significantly greater after warm-up as compared to baseline and after stretching. RMS was not affected by the experimental procedure. In contrast, SampEn was significantly greater after warm-up and stretching as compared to baseline values. %Rec was not modified but %Det for BF muscle was significantly greater after stretching as compared to baseline. The a scaling parameter was significantly lower after warm-up as compared to baseline for ST muscle. From the present results, complexity-based methods applied to the EMG give additional information than linear-based methods. They appeared sensitive to detect EMG complexity increases following warm-up.

Hip and Core Muscle Activation During High-Load Core Stabilization Exercises

BACKGROUND

There is some evidence that high-load lumbar stabilization exercises, such as back bridge, can recruit both local and global muscles.

HYPOTHESIS

Therapeutic exercises would optimize gluteus maximus (GMax), gluteus medius (GMed), multifidus (MF), and transversus abdominis (TrA) activation, while minimizing the activation of the tensor fascia latae (TFL) and erector spinae (ES) muscles in healthy individuals.

DESIGN

Cross-sectional study.

SETTING

Research laboratory.

LEVEL OF EVIDENCE

Level 4.

METHODS

In this cross-sectional study, surface electromyography (EMG) of GMax, GMed, TFL, TrA, MF, and ES was used to quantify the gluteal-to-TFL muscle activation (GTA) index and a ratio of local to global (L/G) lumbar muscles during (1) the elbow-toe exercise in the prone position, (2) the elbow-toe with right left lifted, (3) the hand-knee with left arm and right leg lifted, (4) the back bridge, (5) the back bridge with right leg lifted, (6) the back bridge with left leg lifted, (7) the side bridge with left leg lifted, (8) the side bridge with right leg lifted, and (9) the elbow-toe with right leg horizontally lifted exercises in healthy individuals (20 men, 20 women; age, 25 ± 4 years).

RESULTS

The back bridge exercise with left leg lift generated the highest L/G muscles activity ratio (L/G = 3.35) while the hand-knee exercise yielded the lowest L/G muscles activity ratio (L/G = 1.21). The side bridge exercise with left elbow and foot and lifting the right leg (GTA = 63.78), hand-knee exercise (GTA = 49.62), back bridge (GTA = 28.05), and elbow-toe exercise with left leg horizontally lifted (GTA = 23.02) generated the highest GTA indices, respectively. Meanwhile, the normalized EMG amplitude for GMax was significantly less than the TFL, for elbow-toe exercise (P < 0.001), back bridge with left leg lift (P = 0.001), side bridge exercise with the right elbow and foot and lifting the left leg (P = 0.002), and elbow-toe exercise with right leg horizontally lifted (P < 0.001).

CONCLUSION

The highest GTA indexes were observed during (1) the side bridge lifting the dominant leg and (2) the hand-knee horizontally lifting dominant leg, respectively. The L/G ratio was highest during (1) the back bridge lifting nondominant leg, (2) back bridge, and (3) back bridge lifting dominant leg, respectively. This study supports the use of back bridge exercises to strengthen the MF and side bridges to improve gluteal muscle activation.

CLINICAL RELEVANCE

The highest GTA index was observed in the side bridge lifting the right leg. Highest L/G ratio was in the back bridge with nondominant leg lifted. This study supports the use of back bridge exercises to strengthen the MF. This study supports the use of side bridges to improve gluteal muscle activation.

The Effect of Static Stretching, Mini-Band Warm-Ups, Medicine-Ball Warm-Ups, and a Light Jogging Warm-Up on Common Athletic Ability Tests

Proper warm-up is important for facilitating peak athletic performance and reducing injury risk; yet, warm-up procedures vary considerably amongst coaches and athletes. The purpose of this study was to assess the effect of a static stretching, medicine-ball, and mini-band warm-ups relative to a light jogging warm-up only on athletic ability test performance. It was hypothesized that static stretching would negatively affect performance, while medicine-ball and mini-band warm-ups would positively affect performance relative to light jogging only. Twelve female collegiate soccer players (19.3 ± 1.2y, 65.2 ± 7.5kg, 1.67 ± 0.07m) participated in this study. Athletes completed each warm-up protocol and all of the athletic performance tests over four sessions in a semi-randomized, counterbalanced order. An omnibus MANOVA with vertical jump height, medicine ball throw distance, 10m and 20m sprint time, and T-test time as the dependent variables was not significant indicating that warm up did not have an effect on subsequent athletic ability test performance [Wilks' λ = 0.64, F(15,110) = 1.28, p = 0.23, η2 = 0.14]. Static stretching warm-up did not negatively influence athletic potential compared to mini-band and medicine ball warm-ups, though the most optimal warm-up is likely athlete specific.

Knee Forces During Landing in Men and Women

Sex differences in biomechanics may provide one explanation for the greater incidence of knee injuries in women, but few studies have compared internal forces. In this study, a musculoskeletal model was used to compare male and female, bilateral and unilateral landings based on motion capture and force plate data. Participants were classified as landing medially or laterally loaded based upon the mediolateral load share at the knee (bilateral: p < 0.001, η²=0.452; unilateral: p < 0.001, η² = 0.444). Knee kinematics and ground reaction forces were not different between the two groups (p > 0.05, η² = 0.001 - 0.059), but there were differences in muscular recruitment. Landing strategy did not appear to be dependent on sex. However, for both medially and laterally loaded bilateral landings men had greater gluteal (p = 0.017, η² = 0.085) and hamstrings forces (p < 0.001, η² = 0.183), whereas women had greater quadriceps forces (p = 0.004, η² = 0.116). This study demonstrates an association between muscular recruitment and medially loaded landings. Landing strategy seems to be a function of skill not sex; however, within a particular landing strategy there may be sex differences in muscular activation that contribute to the difference in injury rates.

ASSESSING AND TREATING GLUTEUS MAXIMUS WEAKNESS - A CLINICAL COMMENTARY

The Gluteus Maximus (GM) muscle is the largest and most powerful in the human body. It plays an important role in optimal functioning of the human movement system as well as athletic performance. It is however, prone to inhibition and weakness which contributes to chronic pain, injury and athletic under-performance. As such, understanding how to assess and treat GM dysfunction is an important aspect of sports science and medicine, as it has relevance for injury prevention, rehabilitation and performance enhancement. Despite GMs considerable importance there is little research attempting to translate evidence into practice to support practitioners when faced with 'sleepy glutes'. This clinical commentary discusses the importance of GM for athletic performance and injury risk; factors which contribute to GM dysfunction and then provides evidenced informed approaches to assess and treat GM dysfunction. This can be used as part of rehabilitation or injury prevention practices as well as athletic performance training.

LEVEL OF EVIDENCE

5.

An important role of the biarticular hamstrings is to exert internal/external rotation moments on the tibia during vertical jumping

Most research considering biarticular muscle function has tended to focus on the sagittal plane. Instead, the purpose of this study was to evaluate the internal/external rotation moment arms of the biarticular muscles of the knee, and then to explore their function. The FreeBody musculoskeletal model of the lower limb was used to calculate the moment arms and moments that each of the muscles of the knee exerted on the proximal tibia of 12 athletic males during vertical jumping. Biceps femoris and tensor fascia latae were external rotators of the tibia, whereas semimembranosus, semitendinosus, sartorius, gracilis, popliteus and the patellar tendon were internal rotators. The magnitudes of the internal/external rotation and flexion moments exerted on the tibia by the biarticular hamstrings were similar, suggesting that the creation of internal/external rotation is a key aspect of their role. One potential reason is to stabilise the tibia during femoral extension (and it is argued that it may be helpful to characterise the creation of active joint stability as the stabilisation of one segment during the rotation of an adjacent segment). A second explanation may be to mechanically couple hip abduction when the hip is flexed with internal rotation of the tibia.

Effects of an 8-week strength training intervention on tibiofemoral joint loading during landing: a cohort study

Objectives

To use a musculoskeletal model of the lower limb to evaluate the effect of a strength training intervention on the muscle and joint contact forces experienced by untrained women during landing.

Methods

Sixteen untrained women between 18 and 28 years participated in this cohort study, split equally between intervention and control groups. The intervention group trained for 8 weeks targeting improvements in posterior leg strength. The mechanics of bilateral and unilateral drop landings from a 30 cm platform were recorded preintervention and postintervention, as was the isometric strength of the lower limb during a hip extension test. The internal muscle and joint contact forces were calculated using FreeBody, a musculoskeletal model.

Results

The strength of the intervention group increased by an average of 35% (P<0.05; pre: 133±36 n, post: 180±39 n), whereas the control group showed no change (pre: 152±36 n, post: 157±46 n). There were only small changes from pre-test to post-test in the kinematics and ground reaction forces during landing that were not statistically significant. Both groups exhibited a post-test increase in gluteal muscle force during landing and a lateral to medial shift in tibiofemoral joint loading in both landings. However, the magnitude of the increase in gluteal force and lateral to medial shift was significantly greater in the intervention group.

Conclusion

Strength training can promote a lateral to medial shift in tibiofemoral force (mediated by an increase in gluteal force) that is consistent with a reduction in valgus loading. This in turn could help prevent injuries that are due to abnormal knee loading such as anterior cruciate ligament ruptures, patellar dislocation and patellofemoral pain.

Reliability and Minimal Detectable Change Values for Predictions of Knee Forces during Gait and Stair Ascent Derived from the FreeBody Musculoskeletal Model of the Lower Limb

FreeBody is a musculoskeletal model of the lower limb used to calculate predictions of muscle and joint contact forces. The validation of FreeBody has been described in a number of publications; however, its reliability has yet to be established. The purpose of this study was, therefore, to establish the test-retest reliability of FreeBody in a population of healthy adults in order to add support to previous and future research using FreeBody that demonstrates differences between cohorts after an intervention. We hypothesized that test-retest estimations of knee contact forces from FreeBody would demonstrate a high intra-class correlation. Kinematic and kinetic data from nine older participants (4 men: mean age = 63 ± 11 years; 5 women: mean age = 49 ± 4 years) performing level walking and stair ascent was collected on consecutive days and then analyzed using FreeBody. There was a good level of intra-session agreement between the waveforms for the individual trials of each activity during testing session 1 (R = 0.79-0.97). Similarly, overall there was a good inter-session agreement within subjects (R = 0.69-0.97) although some subjects showed better agreement than others. There was a high level of agreement between the group mean waveforms of the two sessions for all variables (R = 0.882-0.997). The intra-class correlation coefficients (ICC) were very high for peak tibiofemoral joint contact forces (TFJ) and hamstring forces during gait, for peak patellofemoral joint contact forces and quadriceps forces during stair ascent and for peak lateral TFJ and the proportion of TFJ accounted for by the medial compartment during both tasks (ICC = 0.86-0.96). Minimal detectable change (MDC) of the peak knee forces during gait ranged between 0.43 and 1.53 × body weight (18-170% of the mean peak values). The smallest MDCs were found for medial TFJ share (4.1 and 5.8% for walking and stair ascent, respectively, or 4.8 and 6.7% of the mean peak values). In conclusion, the results of this study support the use of FreeBody to investigate the effect of interventions on muscle and joint contact forces at the cohort level, but care should be taken if using FreeBody at the subject level.