The Impact Performance of Headguards for Combat Sports
The Impact Performance of Headguards for Combat Sports
Background/aim To assess the impact energy attenuation performance of a range of headguards for combat sports.
Methods Seven headguards worn during combat sport training or competition, including two Association Internationale de Boxe Amateur (AIBA)-approved boxing models, were tested using drop tests. An International Organization for Standardization (ISO) rigid headform was used with a 5.6 kg drop assembly mass. Tests were conducted against a flat rigid anvil both with and without a boxing glove section. The centre forehead and lateral headguard areas were tested. Peak headform acceleration was measured. Tests from a selection of drop heights and repeated tests on the same headguard were conducted.
Results Headguard performance varied by test condition. For the 0.4 m rigid anvil tests, the best model headguard was the thickest producing an average peak headform acceleration over 5 tests of 48 g compared with 456 g for the worst model. The mean peak acceleration for the 0.4, 0.5 and 0.6 frontal and lateral rigid anvil impact tests was between 32% and 40% lower for the Top Ten boxing model compared with the Adidas boxing model. The headguard performance deterioration observed with repeat impact against the flat anvil was reduced for impacts against the glove section. The overall reduction in acceleration for the combination of glove and headguard in comparison to the headguard condition was in the range of 72–93% for 0.6 and 0.8 m drop tests.
Conclusions The impact tests show the benefits of performance testing in identifying differences between headguard models.
Boxing and martial arts, referred to collectively in this paper as 'combat sports', are sports in which the primary objective of each contestant is 'to strike, kick, hit, grapple with, throw or punch one or more other contestants'. Combat sports are contested at many levels and in a variety of formats, including the Olympic Games. As a result of head and other injury risks in competition and training, headguards and other equipment are often worn. Head injury risks in combat sports include head wounds and concussion. There are various levels of control over equipment used in combat sports, which range from none to government regulations.
The proportion of head injuries reported in boxing varies from 10% to approximately 50% of all injuries depending on study design. In Taekwondo competition, Pieter et al reported that approximately 30% of all injuries in men and 15% in women were to the head and neck region.
Many combat sports have equipment regulations that govern headguards, although few combat sports have performance specifications or refer to standards. Typically, a combat sport will define dimensional criteria: the area of head coverage, the maximum thickness of the headguard and the maximum mass. Unless this approach is supported by performance-based assessment of headguards or formally conducted epidemiological studies, the protective benefits of headguards meeting those dimensional criteria are unknown. There are few performance standards for headguards intended for combat sports.
Helmets are commonly assessed on their ability to reduce the impact force (ie, attenuate impact energy) by dropping an instrumented headform fitted with the helmet from a specified height onto a specified anvil. Drop tests are repeatable and relatively inexpensive. Drop tests have limitations in some areas, for example, the headform's angular kinematics are not measured and/or are constrained by the test method. However, drop tests are able to differentiate between the level of impact performance provided by helmets and form the basis for many successful systems of helmet supply. One characteristic unique to many sports helmets is the requirement for the headguard to function over repeat impacts during a contest, and over many contests and/or training sessions.
Few studies have assessed the protective potential of boxing headguards. All studies have reported that headguards reduce the magnitude of the head's acceleration in the range 15–33%, depending on the impact test method. The objectives of the tests reported in this study are to assess the performance of a range of headguards for combat sports with reference to: impact energy attenuation during a single impact; impact energy attenuation over multiple impacts; and, influence of a boxing glove on impact energy attenuation.
Abstract and Introduction
Abstract
Background/aim To assess the impact energy attenuation performance of a range of headguards for combat sports.
Methods Seven headguards worn during combat sport training or competition, including two Association Internationale de Boxe Amateur (AIBA)-approved boxing models, were tested using drop tests. An International Organization for Standardization (ISO) rigid headform was used with a 5.6 kg drop assembly mass. Tests were conducted against a flat rigid anvil both with and without a boxing glove section. The centre forehead and lateral headguard areas were tested. Peak headform acceleration was measured. Tests from a selection of drop heights and repeated tests on the same headguard were conducted.
Results Headguard performance varied by test condition. For the 0.4 m rigid anvil tests, the best model headguard was the thickest producing an average peak headform acceleration over 5 tests of 48 g compared with 456 g for the worst model. The mean peak acceleration for the 0.4, 0.5 and 0.6 frontal and lateral rigid anvil impact tests was between 32% and 40% lower for the Top Ten boxing model compared with the Adidas boxing model. The headguard performance deterioration observed with repeat impact against the flat anvil was reduced for impacts against the glove section. The overall reduction in acceleration for the combination of glove and headguard in comparison to the headguard condition was in the range of 72–93% for 0.6 and 0.8 m drop tests.
Conclusions The impact tests show the benefits of performance testing in identifying differences between headguard models.
Introduction
Boxing and martial arts, referred to collectively in this paper as 'combat sports', are sports in which the primary objective of each contestant is 'to strike, kick, hit, grapple with, throw or punch one or more other contestants'. Combat sports are contested at many levels and in a variety of formats, including the Olympic Games. As a result of head and other injury risks in competition and training, headguards and other equipment are often worn. Head injury risks in combat sports include head wounds and concussion. There are various levels of control over equipment used in combat sports, which range from none to government regulations.
The proportion of head injuries reported in boxing varies from 10% to approximately 50% of all injuries depending on study design. In Taekwondo competition, Pieter et al reported that approximately 30% of all injuries in men and 15% in women were to the head and neck region.
Many combat sports have equipment regulations that govern headguards, although few combat sports have performance specifications or refer to standards. Typically, a combat sport will define dimensional criteria: the area of head coverage, the maximum thickness of the headguard and the maximum mass. Unless this approach is supported by performance-based assessment of headguards or formally conducted epidemiological studies, the protective benefits of headguards meeting those dimensional criteria are unknown. There are few performance standards for headguards intended for combat sports.
Helmets are commonly assessed on their ability to reduce the impact force (ie, attenuate impact energy) by dropping an instrumented headform fitted with the helmet from a specified height onto a specified anvil. Drop tests are repeatable and relatively inexpensive. Drop tests have limitations in some areas, for example, the headform's angular kinematics are not measured and/or are constrained by the test method. However, drop tests are able to differentiate between the level of impact performance provided by helmets and form the basis for many successful systems of helmet supply. One characteristic unique to many sports helmets is the requirement for the headguard to function over repeat impacts during a contest, and over many contests and/or training sessions.
Few studies have assessed the protective potential of boxing headguards. All studies have reported that headguards reduce the magnitude of the head's acceleration in the range 15–33%, depending on the impact test method. The objectives of the tests reported in this study are to assess the performance of a range of headguards for combat sports with reference to: impact energy attenuation during a single impact; impact energy attenuation over multiple impacts; and, influence of a boxing glove on impact energy attenuation.
