Muscle Activation and Movement Patterns During Prone Hip Extension Exercise in Women

Context:

The consistency of muscle activation order during prone hip extension has been debated.

Objective:

To investigate whether women use a consistent and distinguishable muscle activation order when extending the hip while prone and to explore the effects of verbal cues on muscle activation and movement.

Design:

Single-session, repeated-measures design.

Setting:

University laboratory.

Patients or Other Participants:

Eleven healthy women (age  =  27.7 ± 6.2 years [range, 22–37 years]).

Intervention(s):

We tested the participants under 3 conditions: no cues, cues to contract the gluteal muscles, and cues to contract the hamstrings muscles.

Main Outcome Measure(s):

We measured hip and knee angle and electromyographic data from the gluteus maximus, medial hamstrings, and lateral hamstrings while participants performed prone hip extension from 30° of hip flexion to neutral.

Results:

When not given cues, participants used the consistent and distinguishable muscle activation order of medial hamstrings, followed by lateral hamstrings, then gluteus maximus (195.5 ± 74.9, 100.2 ± 70.3, and 11.5 ± 81.9 milliseconds preceding start of movement, respectively). Compared with the no-cues condition, the gluteal-cues condition resulted in nearly simultaneous onset of medial hamstrings, lateral hamstrings, and gluteus maximus (131.3 ± 84.0, 38.8 ± 96.9, and 45.1 ± 93.4 milliseconds, respectively) (P > .059); decreased activation of the medial hamstrings (P < .03) and lateral hamstrings (P < .024) around the initiation of movement; increased activation of gluteus maximus throughout the movement (P < .001); and decreased knee flexion (P  =  .002). Compared with the no-cues condition, the hamstrings-cues condition resulted in decreased activation of the medial hamstrings just after the initiation of movement (P  =  .028) and throughout the movement (P  =  .034) and resulted in decreased knee flexion (P  =  .003).

Conclusions:

Our results support the contention that the muscle activation order during prone hip extension is consistent in healthy women and demonstrates that muscle timing and activation amplitude and movement can be modified with verbal cues. This information is important for clinicians using prone hip extension as either an evaluation tool or a rehabilitation exercise.     

Classifying Lower Extremity Muscle Fatigue During Walking Using Machine Learning and Inertial Sensors

Fatigue in lower extremity musculature is associated with decline in postural stability, motor performance and alters normal walking patterns in human subjects. Automated recognition of lower extremity muscle fatigue condition may be advantageous in early detection of fall and injury risks. Supervised machine learning methods such as support vector machines (SVMs) have been previously used for classifying healthy and pathological gait patterns and also for separating old and young gait patterns. In this study we explore the classification potential of SVM in recognition of gait patterns utilizing an inertial measurement unit associated with lower extremity muscular fatigue. Both kinematic and kinetic gait patterns of 17 participants (29 ± 11 years) were recorded and analyzed in normal and fatigued state of walking. Lower extremities were fatigued by performance of a squatting exercise until the participants reached 60% of their baseline maximal voluntary exertion level. Feature selection methods were used to classify fatigue and no-fatigue conditions based on temporal and frequency information of the signals. Additionally, influences of three different kernel schemes (i.e., linear, polynomial, and radial basis function) were investigated for SVM classification. The results indicated that lower extremity muscle fatigue condition influenced gait and loading responses. In terms of the SVM classification results, an accuracy of 96% was reached in distinguishing the two gait patterns (fatigue and no-fatigue) within the same subject using the kinematic, time and frequency domain features. It is also found that linear kernel and RBF kernel were equally good to identify intra-individual fatigue characteristics. These results suggest that intra-subject fatigue classification using gait patterns from an inertial sensor holds considerable potential in identifying “at-risk” gait due to muscle fatigue.     

Trunk and Lower Extremity Kinematics During Stair Descent in Women With or Without Patellofemoral Pain

Context

There is limited evidence indicating the contribution of trunk kinematics to patellofemoral pain (PFP). A better understanding of the interaction between trunk and lower extremity kinematics in this population may provide new avenues for interventions to treat PFP.

Objective

To compare trunk and lower extremity kinematics between participants with PFP and healthy controls during a stair-descent task.

Design

Cross-sectional study.

Setting

Research laboratory.

Patients or Other Participants

Twenty women with PFP (age = 22.2 ± 3.1 years, height = 164.5 ± 9.2 cm, mass = 63.5 ± 13.6 kg) and 20 healthy women (age = 21.0 ± 2.6 years, height = 164.5 ± 7.1 cm, mass = 63.8 ± 12.7 kg).

Intervention(s)

Kinematics were recorded as participants performed stair descent at a controlled velocity.

Main Outcome Measure(s)

Three-dimensional joint displacement of the trunk, hip, and knee during the stance phase of stair descent for the affected leg was measured using a 7-camera infrared optical motion-capture system. Pretest and posttest pain were assessed using a visual analogue scale. Kinematic differences between groups were determined using independent-samples t tests. A 2 × 2 mixed-model analysis of variance (group = PFP, control; time = pretest, posttest) was used to compare knee pain.

Results

We observed greater knee internal-rotation displacement for the PFP group (12.8° ± 7.2°) as compared with the control group (8.9° ± 4.4°). No other between-groups differences were observed for the trunk, hip, or other knee variables.

Conclusions

We observed no difference in trunk kinematics between groups but did note differences in knee internal-rotation displacement. These findings contribute to the current knowledge of altered movement in those with PFP and provide direction for exercise interventions.Key Words: anterior knee pain, knee internal rotation, neuromuscular control

Key Points

• Trunk kinematics did not differ between women with and without patellofemoral pain during stair descent.
• Women with patellofemoral pain demonstrated greater knee internal-rotation displacement during stair descent than women without patellofemoral pain.

Patellofemoral pain (PFP) is one of the most frequent chronic injuries among females.^1,2 The causes of PFP are multifactorial, with patellofemoral malalignment commonly accepted as a major contributor.^2,3 Patellofemoral malalignment increases contact pressure within the patellofemoral joint, leading to abnormal cartilage wear and ultimately degenerative changes if left untreated or if conservative treatment options fail.^4,5Lower extremity kinematics may directly influence patellofemoral contact pressure during dynamic tasks. Specifically, the motions of femoral internal rotation, femoral adduction, and knee valgus increase patellofemoral contact pressure.^3,6–8 Extensive research^3,6,9–13 has been conducted to determine alterations in lower extremity kinematics associated with PFP. Lower extremity kinematics may be influenced by other factors that, if recognized, may have a significant effect on treatment interventions for those with PFP.Although there is evidence that trunk kinematics influence lower extremity kinematics and loading,^14–16 few studies have examined trunk kinematics in participants with PFP.^17,18 The presence of aberrant trunk motion in those with PFP and its influence on lower extremity kinematics has been theorized.¹⁹ In the frontal plane specifically, it has been proposed that individuals with PFP who display hip-abductor weakness compensate by elevating the contralateral pelvis and leaning toward the stance limb. This trunk lean has the potential to alter the orientation of the ground reaction force and subsequent external moments acting on the knee in the frontal plane. In the sagittal plane, trunk flexion moves the ground reaction force vectors anteriorly to both the hip and knee joints, thereby increasing the demand of the hip extensors and decreasing the demand of the knee extensors. Decreasing the quadriceps demand decreases the compressive forces within the patellofemoral joint.¹⁹ Given that previous researchers^13,14,16 have demonstrated a relationship between trunk and lower extremity kinematics in a healthy population, it is plausible that individuals with PFP may have altered trunk kinematics that indirectly influence patellofemoral contact pressure.The primary purpose of our study was to compare trunk and lower extremity kinematics during stair descent between women with and without PFP. Our a priori hypotheses were that women with PFP would have greater trunk rotation and lateral flexion toward the stance leg and greater overall trunk flexion. Based on previously reported observations,^20–25 we also expected to observe greater hip adduction, hip internal rotation, and knee valgus in those with PFP.     

Effects of Developmental Stage and Sex on Lower Extremity Kinematics and Vertical Ground Reaction Forces During Landing

Context: The presence or absence of biomechanical differences between the sexes before puberty may provide clues about the onset of adult landing pattern differences, which may help to explain the greater number of anterior cruciate ligament injuries in females than in males and provide the basis for interventions to reduce those injuries.Objective: To identify developmental sex-related and biomechanical differences during vertical jump landings.Design: A 2 x 2 developmental stage (prepubescent or postpubescent) x sex (male or female) between-subjects design.Setting: Controlled laboratory setting.Patients or Other Participants: Thirty prepubescent subjects (15 boys, age = 9.63 +/- 0.95 years; 15 girls, age = 9.19 +/- 1.00 years) and 28 postpubescent subjects (14 men, age = 23.57 +/- 3.23 years; 14 women, age = 24.22 +/- 2.27 years).Intervention: Subjects performed a vertical jump to a target set at 50% of their maximum vertical jump height ability.Main Outcome Measure(s): Hip and knee kinematics of the dominant lower extremity and vertical ground reaction forces during impact were analyzed.Results: We found significant main effects for developmental stage. Children demonstrated greater knee valgus and less hip flexion at initial contact and at maximum vertical force, less knee flexion at maximum vertical force, greater maximum vertical force and impulse, and a shorter time to maximum vertical force than the adults. No sex differences were found among the biomechanical variables measured.Conclusions: The presence of significant biomechanical differences between children and adults suggests that physical development influences landing patterns. Sex does not appear to influence landing patterns during a 50% maximum vertical jump landing. These findings add to the body of knowledge regarding developmental and sex comparisons in a functional landing task.     

Effects of Plyometric Training on Muscle-Activation Strategies and Performance in Female Athletes

OBJECTIVE: To evaluate the effects of plyometric training on muscle-activation strategies and performance of the lower extremity during jumping exercises. SUBJECTS: Twenty healthy National Collegiate Athletic Association Division I female athletes. DESIGN AND SETTING: A pretest and posttest control group design was used. Experimental subjects performed plyometric exercises 2 times per week for 6 weeks. MEASUREMENTS: We used surface electromyography to assess preparatory and reactive activity of the vastus medialis and vastus lateralis, medial and lateral hamstrings, and hip abductors and adductors. Vertical jump height and sprint speed were assessed with the VERTEC and infrared timing devices, respectively. RESULTS: Multivariate analyses of variance revealed significant (P <.05) increases in firing of adductor muscles during the preparatory phase, with significant interactions for area, mean, and peak. A Tukey honestly significant difference post hoc analysis revealed significant increases in preparatory adductor area, mean, and peak for experimental group. A significant (P =.037) increase in preparatory adductor-to-abductor muscle coactivation in the experimental group was identified, as well as a trend (P =.053) toward reactive quadriceps-to- hamstring muscle coactivation in the experimental group. Pearson correlation coefficients revealed significant between-groups adaptations in muscle activity patterns pretest to posttest. Although not significant, experimental and control subjects had average increases of 5.8% and 2.0% in vertical jump height, respectively. CONCLUSIONS: The increased preparatory adductor activity and abductor-to-adductor coactivation represent preprogrammed motor strategies learned during the plyometric training. These data strongly support the role of hip-musculature activation strategies for dynamic restraint and control of lower extremity alignment at ground contact. Plyometric exercises should be incorporated into the training regimens of female athletes and may reduce the risk of injury by enhancing functional joint stability in the lower extremity.     

产后女性进行盆底肌康复治疗对其性功能障碍的改善效果

目的:探究产后女性进行盆底肌康复治疗对其性功能障碍的改善效果。方法:随机选取我院收治的120例产后女性患者,按照数字表法分组,将其分为试验组、对照组两组,对照组采用常规康复治疗,试验组开展盆底肌康复训练治疗,对比分析两组患者预后情况。结果:试验组女性患者治疗后3个月、6个月的性交频率与对照组患者相比明显较高,差异有统计学意义(t=-17.0692,-20.9648;P0.05)。试验组女性患者治疗后3个月、6个月的性功能评分与对照组患者相比明显较高,差异有统计学意义(t=-18.1220,-10.8083;P0.05)。结论:产后女性进行盆底肌康复治疗后,有利于提高性功能,增加性交频率,预后效果显著,临床意义重大。     

Abdominal Muscle Activity While Performing Trunk-Flexion Exercises Using the Ab Roller, ABslide, FitBall, and Conventionally Performed Trunk Curls

OBJECTIVE: To compare the surface electromyographic activity of the abdominal musculature and rectus femoris (RF) muscle during trunk-flexion exercises using 3 abdominal exercise devices (Ab Roller, ABslide, and FitBall) and the traditional trunk curl. DESIGN AND SETTING: Each subject performed approximately 15 repetitions for each exercise condition. A repeated-measures, one-way multivariate analysis of variance was used to compare the mean integrated electric activity value for each muscle during each exercise condition. SUBJECTS: A total of 10 male and 13 female collegiate undergraduate students. MEASUREMENTS: Surface electromyographic activity was recorded for the upper rectus abdominis (URA), lower rectus abdominis (LRA), external oblique (EO), and RF during 5 consecutive repetitions of each exercise bout. The signal was amplified by a factor of 1000, rectified, and integrated. These integrated values were then divided by the time value for each exercise to give the mean integrated electromyography value. RESULTS: A significant difference existed among exercise conditions for the RF (P <.0001), with the ABslide and the FitBall having greater electric activity than the other exercise conditions. Activity was significantly different (P <.0009) for the URA, with the ABslide having the least electric activity. For the EO, exercising with the ABslide produced significantly greater electric activity (P <.0001) than all other exercise conditions. No significant difference was found across exercise conditions for the LRA (P <.051). CONCLUSIONS: Performing abdominal exercises with the Ab Roller, ABslide, and FitBall did not elicit greater activity of the URA and LRA than performing traditional trunk curls. Use of the ABslide elicited greater EO activity and significantly less URA activity than the other 3 modes. Both the ABslide and FitBall resulted in greater involvement of the hip flexors, an undesirable feature of abdominal exercises.     

不同地面对跑步下肢运动生物力学的影响

诸多因素会影响跑步运动损伤的发生,其中内在因素包括人体解剖学因素、受伤史、下肢运动生物力学和运动中的神经肌肉控制等,外在因素包括训练方法、跑步鞋、跑步路面等。跑步路面被认为是造成跑步运动损伤发生的重要潜在风险因素之一。总结不同地面对跑步下肢运动学、动力学、神经肌肉调控、运动损伤方面的影响,发现在不同地面跑步时,人体可能通过自身的神经肌肉调节功能进行运动学调整以获得动力学适应,调节下肢刚度以获得相似的冲击负荷。但是目前关于在不同路面上跑步的生物力学变化,多数研究只关注于运动学、动力学和神经肌肉调控中的某一方面,缺乏更进一步具体的三维运动生物力学数据,以及针对这种生物力学调整的具体神经肌肉调控机制。     

下肢康复训练减重支撑系统的研究现状

目的：下肢减重康复训练已成为下肢功能康复重要的治疗方法之一,因其在恢复步行能力、纠正步态、改善平衡、减轻肌肉痉挛、减少心肺负荷等方面具有优势,故下肢减重康复训练越来越受到众多学者的关注。然而,下肢康复训练减重支撑系统是下肢减重康复训练必不可少的一部分,因为合理舒适的减重支撑系统对于减重康复训练的效果具有较大的影响。因此随着科技的发展下肢康复训练减重支撑系统也在一步步改进以满足患者的需求。本文对下肢康复训练减重支撑系统的国内外研究现状进行综述,并展望其发展趋势。方法：通过查阅国内外相关文献,同时融合本单位的相关经验分析总结进行综述。结果：目前所使用的减重支撑系统（BWS）主要有悬吊减重系统、斜床背部支撑减重系统、水浮力减重系统、空气压差式减重系统等。结论：上述几种减重系统都有其缺点,在使用时具有一定的局限性,因此需要进行相关技术的进一步改进以设计出更加自然、合理的下肢减重支撑系统以满足更多患者的需求,故下肢康复训练减重支撑系统具有广阔的发展空间和良好的应用前景。     

人工髋关节置换术后并发有症状下肢深静脉血栓临床分析

目的：探讨有症状下肢深静脉血栓（DVT）的发生率、临床特点及药物预防DVT的可行性。方法：2006年1月～2009年12月行人工髋关节置换术232例,术后连续腹壁脐周皮下注射低分子肝素钙4000U／d×10d,口服阿司匹林1片／d×30d。其中13例分别于术后第3～9天先后出现术侧下肢循环障碍临床表现,结合下肢深静脉彩超或下肢深静脉造影检查,均确诊为有症状下肢DVT,并立即行取栓术治疗。结果：13例患者行取栓术后,临床症状消失,Homans征和Neuhof征转为阴性。2例患者术后伤口渗出增加,细菌培养阴性,停用低分子肝素钙后伤口渗出减少,至术后2周伤口完全愈合。出院后随访1．5个月,再次行下肢深静脉彩超或下肢深静脉造影,未发现有血栓形成。结论：术前和术后患肢发生不明原因的肿痛时,应警惕下肢DVT的存在。早期诊断DVT,早期手术,并规范应用抗凝剂,联合早期功能锻炼,可以有效的防治下肢DVT。     

Comparison of the Safety and Effectiveness of Lower Extremity Artery Bypass Grafting and Endovascular Angioplasty in the Treatment of Lower Extremity Arteriosclerosis Obliterans in the Elderly

Objective:To compare the safety and effectiveness of lower extremity artery bypass grafting and endovascular angioplasty in the treatment of lower extremity arteriosclerosis obliterans in the elderly.Methods:The data of 87 elderly patients with lower extremity arteriosclerosis obliterans treated in our hospital from August 2015 to August 2017 were analyzed retrospectively.According to the different treatment methods,they were divided into angioplasty group(n=45,intravascular angioplasty) and bypass grafting group(n=42,lower extremity artery bypass grafting).The success rate,hemodynamics of dorsalis pedis artery and nerve conduction of lower extremity were compared between the two groups Velocity,VAS score,late target vessel lumen loss(LLL),patency rate,restenosis rate,ankle brachial index(ABI) and clinical adverse events.Results:There was no significant difference between angioplasty group and bypass group(P0.05).One month after operation,the hemodynamics of dorsalis pedis artery and nerve conduction velocity of lower limbs in the two groups were better than those before operation,the difference was statistically significant(P0.05),but there was no significant difference between the two groups(P0.05).The VAS score of the two groups was significantly lower than that of the preoperative group(P0.05),but there was no significant difference between the two groups(P0.05).The ABI of the two groups was significantly improved after operation,the difference was statistically significant(P0.05),but there was no significant difference between the groups at each time point(P0.05).There was no significant difference in LLL,patency rate and restenosis rate between the two groups(P0.05).There was statistical difference in the incidence of complications between the two groups(P0.05).During the follow-up period,no serious adverse events such as death or amputation occurred in both groups.Conclusion:Endovascular angioplasty and lower extremity artery bypass grafting have the same clinical effect in the treatment of elderly patients with lower extremity arteriosclerosis obliterans,which are safe and feasible.     

系统化康复护理在老年髋部骨折患者围手术期中的应用

目的 研究系统化康复护理对老年髋部骨折手术患者的影响。方法 选取2016年7月~2018年6月我院收治的老年髋部骨折患者125例,随机分为观察组（63例）和对照组（62例）。对照组给予常规护理,观察组在常规护理基础上给予系统化康复护理,比较两组护理前、术后1个月、术后3个月Harris髋关节功能评分和Barthel 指数评分,住院费用、住院时间及术后并发症发生率。结果 两组护理后Harris髋关节功能评分、Barthel 指数评分、住院时间及住院费用、术后并发症发生率比较,差异均有统计学意义（P＜0.05）。结论 系统化康复护理能有效改善老年髋部骨折手术患者的关节活动功能,缩短住院时间,减少住院费用,提高生活质量及生活自理能力。     

Effects of Back-Support Exoskeleton Use on Lower Limb Joint Kinematics and Kinetics During Level Walking

We assessed the effects of using a passive back-support exoskeleton (BSE) on lower limb joint kinematics and kinetics during level walking. Twenty young, healthy participants completed level walking trials while wearing a BSE (backX^TM) with three different levels of hip-extension support torque (i.e., no torque, low, and high) and in a control condition (no-BSE). When hip extension torques were required for gait—initial 0–10% and final 75–100% of the gait cycle—the BSE with high supportive torque provided ~ 10 Nm of external hip extension torque at each hip, resulting in beneficial changes in participants’ gait patterns. Specifically, there was a ~ 10% reduction in muscle-generated hip extension torque and ~ 15–20% reduction in extensor power. During the stance-swing transition, however, BSE use produced undesirable changes in lower limb kinematics (e.g., 5–20% increase in ankle joint velocity) and kinetics (e.g., ~ 10% increase in hip flexor, knee extensor, and ankle plantarflexor powers). These latter changes likely stemmed from the need to increase mechanical energy for propelling the leg into the swing phase. BSE use may thus increase the metabolic cost of walking. Whether such use also leads to muscle fatigue and/or postural instability in long-distance walking needs to be confirmed in future work.

     

A Comparison of Thermoregulation With Creatine Supplementation Between the Sexes in a Thermoneutral Environment

OBJECTIVE: To compare the effect of creatine supplementation on thermoregulation in males and females during exercise in a thermoneutral environment. DESIGN AND SETTING: Male and female subjects participated in 30 minutes of cycle ergometry in nonsupplemented (NS) and creatine-supplemented (Cr) conditions at 70% to 75% of predetermined peak oxygen consumption. SUBJECTS: Ten male and ten female subjects were evaluated with and without creatine supplementation. MEASUREMENTS: Analyses were performed during exercise for core temperature and mean skin temperature using two 2 x 2 x 7 mixed-factorial analyses of variance (ANOVAs). We compared mean differences between NS and Cr conditions and sex for heart rate, systolic blood pressure, and diastolic blood pressure using 3 2 x 2 x 4 mixed-factorial ANOVAs. Three 2 x 2 mixed-factorial ANOVAs were computed to examine differences between sex and conditions for the following variables: nude body weight and blood urea nitrogen before and after exercise and urine specific gravity. RESULTS: Significant time effects were found for core temperature, skin temperature, heart rate, and diastolic blood pressure. Time effect and difference between the sexes for systolic blood pressure were both significant. Differences in nude body weight and blood urea nitrogen before and after exercise were greater for males, but there was no difference between conditions. No significant difference between sex and condition for urine specific gravity was noted. CONCLUSIONS: Short-term creatine supplementation did not affect thermoregulation between the sexes when exercising in a thermoneutral environment. Differences in changes in nude body weight before and after exercise may be due to a higher sweating rate in males versus females. Differences in blood urea nitrogen before and after exercise between the sexes may be due to a reduced glomerular filtration rate coupled with greater muscle creatine breakdown in males.     

基于减重步行训练的下肢康复机器人结构设计与分析

提出了一款基于气囊式减重原理的下肢康复训练机器人。它集主动训练与被动训练、静态平衡与功能评定于一体,适用于下肢偏瘫的脑卒中患者。装置的机械结构包括减重支持结构、步行器、拉伸锁定结构配合U型架、箱体结构和外框架辅助结构。对跑步机这一运动部件用SolidWorks软件进行三维建模,并用有限元分析软件Ansys进行应力计算表明:跑步机最大应力值为3.593 2 MPa,最大变形值为1.062 7 mm,均在材料容许范围以内,验证了设计的合理性与可行性。     

老年髋部骨折术后下肢深静脉血栓形成的预防及护理干预效果分析

目的 探析老年髋部骨折术后下肢深静脉血栓形成的预防和护理措施。方法 将2015年1月~2017年1月我院接收的老年髋部骨折术后患者90例进行回顾性分析,给予预防与护理措施,分析措施实施后患者下肢深静脉血栓形成形成发生率、住院时间及生活质量改善的情况。结果 患者下肢深静脉血栓形成发生率、住院时间、生存质量显著优于预防及护理措施实施前,P<0.05表示有统计学意义。结论 将预防与护理干预措施应用在老年髋部骨折术后患者临床护理中可有效降低下肢深静脉血栓形成发生率,改善患者生活质量,促进患者尽快康复。     

The Influence of Body Mass Index,Sex, &amp; Muscle Activation on Pressure Distribution During Lateral Falls on the Hip

Hip fracture incidence rates are influenced by body mass index (BMI) and sex, likely through mechanistic pathways that influence dynamics of the pelvis-femur system during fall-related impacts. The goal of this study was to extend our understanding of these impact dynamics by investigating the effects of BMI, sex, and local muscle activation on pressure distribution over the hip region during lateral impacts. Twenty participants underwent “pelvis-release experiments” (which simulate a lateral fall onto the hip), including muscle-‘relaxed’ and ‘contracted’ trials. Males and low-BMI individuals exhibited 44 and 55% greater peak pressure, as well as 66 and 56% lower peripheral hip force, compared to females and high-BMI individuals, respectively. Local muscle activation increased peak force by 10%, contact area by 17%, and peripheral hip force by 11% compared to relaxed trials. In summary, males and low-BMI individuals exhibited more concentrated loading over the greater trochanter. Muscle activation increased peak force, but this force was distributed over a larger area, preventing increased localized loading over the greater trochanter. These findings suggest potential value in incorporating sex, gender, and muscle activation-specific force distributions as inputs into computational tissue-level models, and have implications for the design of personalized protective devices including wearable hip protectors.