Effects of fatigue on lower limb, pelvis and trunk kinematics and muscle activation: Gender differences

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Abstract

Background: Muscle fatigue is associated with biomechanical changes that may lead to anterior cruciate ligament (ACL) injuries. Alterations in trunk and pelvis kinematics may also be involved in ACL injury. Although some studies have compared the effects of muscle fatigue on lower limb kinematics between men and women, little is known about its effects on pelvis and trunk kinematics. The aim of the study was to compare the effects of fatigue on lower limb, pelvis and trunk kinematics and muscle activation between men and women during landing. Methods: The participants included forty healthy subjects. We performed kinematic analysis of the trunk, pelvis, hip and knee and muscle activation analysis of the gluteal muscles, vastus lateralis and biceps femoris, during a single-leg landing before and after fatigue. Results: Men had greater trunk flexion than women after fatigue. After fatigue, a decrease in peak knee flexion and an increase in Gmax and BF activation were observed. Conclusion: The increase in the trunk flexion can decrease the anterior tibiofemoral shear force resulted from the lower knee flexion angle, thereby decreasing the stress on the ACL.

Introduction

One of the most common injuries during sports activity is anterior cruciate ligament (ACL) disruption (Yu and Garrett, 2007). ACL injury tends to occur without contact in activities that involve cutting, pivoting, decelerating, or landing from a jump (Ireland, 1999, Hewett et al., 2005, Yu and Garrett, 2007). In addition, women are four to six times more prone to ACL injuries than men, when participating in the same sporting activity (Boden et al., 2000).

There are several intrinsic and extrinsic factors linked to the noncontact ACL injury disparity between genders (Arendt and Dick, 1995). Fatigue is an extrinsic factor affecting the neurological and musculoskeletal systems (Chappell et al., 2005). Most athletic injuries occur in the later stages of activities and competition, indicating that fatigue may play a crucial role in the incidence of injury (Hawkins and Fuller, 1999, Hawkins et al., 2001, Price et al., 2004). Muscle fatigue can lead to a reduced ability of the muscles to generate strength (Lattier et al., 2004) and altered neuromuscular control (McLean et al., 2007). In this context, fatigue causes abnormal and potentially hazardous movement strategies, increasing the risk of a noncontact ACL injury during landing (Santamaria and Webster, 2010).

Several studies have evaluated the effects of fatigue on landing biomechanics, demonstrating the influence of fatigue on lower limb kinematics and differences between genders (McLean et al., 2007, Kernozek et al., 2008, Gehring et al., 2009, Brazen et al., 2010, Liederbach et al., 2014). The most commonly studied variables are knee and hip kinematics in the sagittal and frontal planes. However, studies involving the effects of lower limb muscle fatigue on landing kinematics in subjects of different genders did not include assessments of proximal segments, such as the pelvis or trunk.

Decreases of lower limb muscle activation due to fatigue can result in changes in pelvis and trunk position. The influence of fatigue on trunk position is an important aspect because it can change the loads on the knee joint and the stress on the ACL (Kulas et al., 2012). In the sagittal plane, the trunk extension is a common used strategy to decrease the demand on fatigued/weak hip extensor muscles (Powers, 2010). However, a smaller trunk flexion during landing increases the quadriceps muscle activation (Blackburn and Padua, 2009) and, consequently, the anterior tibiofemoral shear force and the stress on the ACL (especially with the knee close to full extension) (Kulas et al., 2012).

In the frontal plane, a decreased activation of the hip abductor muscles due to fatigue could lead to an excessive contralateral pelvic drop (Trendelenburg sign). A typical compensation for this activation deficit is ipsilateral trunk lean (towards to the support limb) (Powers, 2010). However, ipsilateral trunk lean can cause the ground reaction force vector to pass laterally with respect to the knee joint center, creating an abduction moment at the knee (Powers, 2010, Nakagawa et al., 2012). This is an important aspect, since Hewett et al. (2005) reported that the knee abduction moment is a predictor of ACL injury in female athletes.

To the best of the authors’ knowledge, only Liederbach et al. (2014) evaluated the influence of lower limb muscle fatigue on trunk kinematics during landing and compared these data between genders, which suggests that more studies are necessary. Specifically, Liederbach et al. (2014) found an increase in trunk flexion and ipsilateral trunk lean during the single-leg landing after fatigue, but no difference between men and women. However, these authors did not evaluate the effect of fatigue on lower limb muscles activation. Therefore, it is unclear whether there is a relationship between changes in muscle activation and changes in trunk position after the application of a fatigue protocol for the lower limb muscles.

The purpose of this study was to compare the effects of lower limb muscle fatigue on knee, hip, pelvis and trunk kinematics and lower limb muscle activity between men and women during the single-leg drop vertical jump landing. Based on the biomechanical differences between men and women, the hypothesis of this study is that fatigue will alter in different ways the landing biomechanics in men and women.

Section snippets

Participants

Based on a previous study (Kernozek et al., 2008) with statistical significance set at a two-sided level of 0.05, a power of 0.8, and a correlation among repeated measures of 0.5, we estimated that we needed a minimum of 18 subjects per group. Participation was voluntary, and all participants signed a written informed consent form, and the study was approved by the University’s Ethics Committee for Human Investigations (no. 24379). For this study, 40 healthy recreational athletes between the

Statistical analysis

All statistical analyses were performed using SPSS statistical software (version 17.0; SPSS, Inc., IL). All data were expressed as the mean and standard deviation. The Student’s t-tests for independent samples were used to verify the differences in the demographic characteristics of the groups. The kinematic and EMG data were considered dependent variables. The effects of fatigue on the dependent variables were evaluated by a two-way (gender X fatigue) ANOVA with a mixed-model design, with the

Results

No significant difference was observed between participants in terms of the amount of physical activity practice per week (men 4.3 ± 1.1 h per week and women 3.8 ± 0.9 h per week; P > 0.05). Men completed an average of 10.4 ± 2.8 successful series of the fatigue protocol and reported a mean Borg rating of 8.2 ± 1.2. Women completed an average of 9.1 ± 3.0 successful series of the fatigue protocol and reported a mean Borg rating of 8.2 ± 0.8; there were no significant differences between the groups for these

Discussion

The aim of this study was to evaluate the effects of muscle fatigue in trunk, pelvis, hip and knee kinematics, and lower limb muscle activation between men and women. The hypothesis that fatigue would alter landing biomechanics in men and women, but with different alterations between genders was confirmed.

The main innovation of this study was the evaluation of the effects of fatigue on the trunk and pelvis angles. The change in the trunk position can alter the loads on the knee joint (Powers,

Conclusions

The increase in the peak trunk flexion may help to decrease the anterior tibiofemoral shear force resulted from lower knee flexion angle, thereby decreasing the stress on the ACL. Men presented greater trunk flexion after fatigue compared to women, suggesting that males were able to better adapt to the fatigue condition.

Acknowledgments

The authors are grateful for the support obtained from the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Conselho Nacional de Desenvolvimento Científico e Tecnológico (306848/2012-0) and Fundação de Amparo à Pesquisa do Estado de São Paulo (2014/10506-1).

Giovanna Camparis Lessi. Received the MSc degree in Physical Therapy in 2011 and a Ph.D in Physical Therapy in 2015, both from the Federal University of São Carlos. Her PhD focused on biomechanics adaptations after fatigue in individuals with ACL injury. Her special interests include biomechanical changes following knee injury and signal processing of human movement.

References (35)

  • D.M. Brazen et al.

    The effect of fatigue on landing biomechanics in single-leg drop landings

    Clin. J. Sport Med.

    (2010)
  • T.J. Brindle et al.

    Electromyographic changes in the gluteus medius during stair ascent and descent in subjects with anterior knee pain

    Knee Surgery, Sport Traumatol. Arthrosc.

    (2003)
  • J.D. Chappell et al.

    Effect of fatigue on knee kinetics and kinematics in stop-jump tasks

    Am. J. Sports Med.

    (2005)
  • R.D. Hawkins et al.

    A prospective epidemiological study of injuries in four English professional football clubs

    Br. J. Sports Med.

    (1999)
  • R.D. Hawkins et al.

    The association football medical research programme: an audit of injuries in professional football

    Br. J. Sports Med.

    (2001)
  • B.L. Heinert et al.

    Hip abductor weakness and lower extremity kinematics during running

    J. Sport Rehabil.

    (2008)
  • T.E. Hewett et al.

    Biomechanical measures of neuromuscular control and valgus loading of the knee predict anterior cruciate ligament injury risk in female athletes: a prospective study

    Am. J. Sports Med.

    (2005)
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    Giovanna Camparis Lessi. Received the MSc degree in Physical Therapy in 2011 and a Ph.D in Physical Therapy in 2015, both from the Federal University of São Carlos. Her PhD focused on biomechanics adaptations after fatigue in individuals with ACL injury. Her special interests include biomechanical changes following knee injury and signal processing of human movement.

    Ana Flávia dos Santos. Received the MSc degree in Physical Therapy in 2014 from the Federal University of São Carlos. She is currently a Ph.D. candidate at Federal University of São Carlos. Her research interests focuses on biomechanical adaptations in individuals with patellofemoral pain during running.

    Luis Fylipe Batista. Received a B.Sc in Physical Therapy from Federal University of São Carlos in 2015. He is currently finishing his specialization course in sports rehabilitation at the Federal University of São Paulo.

    Gabriela Clemente de Oliveira. Received a B.Sc in Physical Therapy from Federal University of São Carlos in 2014. In 2015 she specialized in sports rehabilitation at the Federal University of São Paulo. At present she works in clinic where she is specialized in athlete rehabilitation.

    Fábio Viadanna Serrão. Received the B.Sc in Physical Therapy from Methodist University of Piracicaba (1996), MSc degree in Physical Therapy from the Federal University of São Carlos (1998) and Ph.D in Physical Therapy from the Federal University of São Carlos (2004). He is currently Associate Professor of the Federal University of São Carlos at the Physical Therapy department. His research interests are assessment and rehabilitation in lower limb injuries and biomechanics.

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