OBJECTIVES: To evaluate the clinical characteristics, ground reaction force (GRF), and function of the plantar muscles and dorsiflexors of the ankle in runners with and without Achilles tendinopathy (AT) and in non-runners. METHODS: Seventy-two participants (42 men, 30 women; mean age: 37.3±9.9 years) were enrolled in this cross-sectional study and divided into three groups: AT group (ATG, n=24), healthy runners’ group (HRG, n=24), and non-runners’ group (NRG, n=24). Both ankles were evaluated in each group. The American Orthopedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale was used for clinical and functional evaluation. GRF was evaluated using force plates and muscle strength was evaluated using an isokinetic dynamometer. RESULTS: The AOFAS scores were lower in the ATG. The strike impulse was higher in the ATG than in the HRG and NRG. However, GRF was similar among the groups. The ATG exhibited lower total work at 120°/s speed than the HRG. The peak torque in concentric dorsiflexion was lower in the NRG than in the ATG and HRG. The peak torque and total work in concentric plantar flexion were lower in the NRG than in the ATG. The peak torque and total work in eccentric plantar flexion were lower in the NRG than in the ATG and HRG. CONCLUSION: Runners with AT showed higher strike impulse, lower muscle strength of the plantar flexors, and higher clinical and functional damage.

INTRODUÇÃO Apesar dos inúmeros benefícios para a saúde humana e considerando o aumento da corrida como exercício, atividade mundialmente popular, este tipo de esporte pode ser a causa de uma série de diferentes lesões. O pé, tornozelo e parte inferior da perna compreendem quase 40% das lesões. No entanto, a etiologia destas lesões permanece mal compreendida. OBJETIVO: investigar as causas do aparecimento da lesão de esforço em corredores. MÉTODOS: Uma busca sistemática foi realizada nas seguintes bases de dados: Bireme, PubMed e PEDro, selecionando-se ensaios clínicos, casos controle, estudos prospectivos e de corte transversal. RESULTADOS: A pesquisa através dos descritores rendeu 324 referências. Usando critérios de inclusão pré-definidos (estudos de casos, ensaios clínicos, estudos prospectivos e estudos transversais que abordavam adultos corredores indivíduos, amador ou profissional) permaneceram 68 artigos; 24 citações foram excluídos depois de ler o título, e 35 foram excluídos após a leitura do resumo e do texto integral. Portanto nove estudos que preencheram os critérios de análise foram incluídos. CONCLUSÃO: A etiologia das lesões de esforço em corredores é multifatorial. Esta revisão mostrou que a distância, tipo de solo e calçados, bem como uma história de lesões prévias, alterações biomecânicas como o aumento da dorsiflexão e eversão do tornozelo, e uma maior flexão do joelho são fatores de risco que influenciam a ocorrência dessas lesões.

INTRODUCTION: In spite of the numerous benefits to human health and given the increase of running as an exercise that has become popular worldwide, this type of sport may be the cause of a number of different injuries. The foot, ankle and lower leg comprise almost 40% of the injuries. However, the etiology of these types of injury is still not completely understood. OBJECTIVE: To investigate the causes of the onset of overuse injury in runners. METHODS: A systematic search of the electronic database was made: Bireme, Pubmed and PEDro, which were selected that addressed clinical trials, control cases, prospective and cross-sectional studies. RESULTS: The search through the descriptors yielded 324 references. Using our predefined inclusion criteria (case studies, clinical trials, prospective studies and cross studies that addressed adult runners, amateur or professional) 68 articles remained; 24 citations were excluded after reading the title, and 35 were excluded after reading the abstract and the full text. Therefore nine studies that met the criteria for analysis were included. CONCLUSION: The etiology of overuse injuries in runners is multifactorial. This review showed that distance, soil type and footwear, as well as a history of previous injuries, biomechanical changes such as increased dorsiflexion and eversion ankle, and greater knee flexion are risk factors that influence the occurrence of these injuries.