title: Reliability of Repeated Nordic Hamstring Strength in Rugby Players Using a Load Cell Device

authors: Chavarro-Nieto, Christian

subjects: football

abstract: Hamstring strain injuries are one of the most common injuries in Rugby Union players, representing up to 15% of all sustained injuries. The Nordic eccentric hamstring test assesses the maximal hamstring eccentric strength and imbalances between limbs. Asymmetries and deficits in hamstring strength between legs are commonly assessed and used as screening methods to prevent injuries which can only be proven effective if hamstring strength measures are reliable over time. We conducted a repeated-measures reliability study with 25 male Rugby Union players. Nordic eccentric strength and bilateral strength balance was assessed. Three testing sessions were undertaken over three consecutive weeks. Intrasession and intersession reliabilities were assessed using typical errors (TE), coefficient of variations (CV), and intraclass correlation coefficients (ICC). Our results showed good intrasession reliability (ICC = 0.79-0.90, TE = 26.8 N to 28.9 N, CV = 5.5% to 6.7%), whilst intersession reliability was fair for mean and the max (ICC = 0.52-0.64, TE = 44.1 N to 55.9 N, CV from 7.4% to 12.5%). Regarding the bilateral strength balance ratios, our results showed good intrasession reliability (ICC = 0.62-0.89, TE = 0.5, CV = 4.4% to 7.2%), whilst the intersession reliability for mean and max values was fair (ICC = 0.52-0.54) with a good absolute intersession reliability CV ranging from 8.2% to 9.6%. Assessing the Nordic eccentric hamstring strength and the bilateral strength balance in Rugby players using a load cell device is a feasible method to test, and demonstrated good intrasession and fair intersession reliability. Nordic eccentric strength assessment is a more practical and functional test than isokinetic; we provide data from Rugby Union players to inform clinicians, and to establish normative values in this cohort.

text: Reliability of Repeated Nordic Hamstring Strength in Rugby Players Using a Load Cell Device Hamstring strain injuries are one of the most common injuries in Rugby Union players, representing up to 15% of all sustained injuries. The Nordic eccentric hamstring test assesses the maximal hamstring eccentric strength and imbalances between limbs. Asymmetries and deficits in hamstring strength between legs are commonly assessed and used as screening methods to prevent injuries which can only be proven effective if hamstring strength measures are reliable over time. We conducted a repeated-measures reliability study with 25 male Rugby Union players. Nordic eccentric strength and bilateral strength balance was assessed. Three testing sessions were undertaken over three consecutive weeks. Intrasession and intersession reliabilities were assessed using typical errors (TE), coefficient of variations (CV), and intraclass correlation coefficients (ICC). Our results showed good intrasession reliability (ICC = 0.79-0.90, TE = 26.8 N to 28.9 N, CV = 5.5% to 6.7%), whilst intersession reliability was fair for mean and the max (ICC = 0.52-0.64, TE = 44.1 N to 55.9 N, CV from 7.4% to 12.5%). Regarding the bilateral strength balance ratios, our results showed good intrasession reliability (ICC = 0.62-0.89, TE = 0.5, CV = 4.4% to 7.2%), whilst the intersession reliability for mean and max values was fair (ICC = 0.52-0.54) with a good absolute intersession reliability CV ranging from 8.2% to 9.6%. Assessing the Nordic eccentric hamstring strength and the bilateral strength balance in Rugby players using a load cell device is a feasible method to test, and demonstrated good intrasession and fair intersession reliability. Nordic eccentric strength assessment is a more practical and functional test than isokinetic; we provide data from Rugby Union players to inform clinicians, and to establish normative values in this cohort.

year: 2022-12-13

title: Temporal dynamics of geothermal microbial communities in Aotearoa-New Zealand

authors: Power, Jean Florence

abstract: Microbial biogeography studies, in particular for geothermal-associated habitats, have focused on spatial patterns and/or individual sites, which have limited ability to describe the dynamics of ecosystem behaviour. Here, we report the first comprehensive temporal study of bacterial and archaeal communities from an extensive range of geothermal features in Aotearoa-New Zealand. One hundred and fifteen water column samples from 31 geothermal ecosystems were taken over a 34-month period to ascertain microbial community stability (control sites), community response to both natural and anthropogenic disturbances in the local environment (disturbed sites) and temporal variation in spring diversity across different pH values (pH 3, 5, 7, 9) all at a similar temperature of 60–70°C (pH sites). Identical methodologies were employed to measure microbial diversity via 16S rRNA gene amplicon sequencing, along with 44 physicochemical parameters from each feature, to ensure confidence in comparing samples across timeframes. Our results indicated temperature and associated groundwater physicochemistry were the most likely parameters to vary stochastically in these geothermal features, with community abundances rather than composition more readily affected by a changing environment. However, variation in pH (pH ±1) had a more significant effect on community structure than temperature (±20°C), with alpha diversity failing to adequately measure temporal microbial disparity in geothermal features outside of circumneutral conditions. While a substantial physicochemical disturbance was required to shift community structures at the phylum level, geothermal ecosystems were resilient at this broad taxonomic rank and returned to a pre-disturbed state if environmental conditions re-established. These findings highlight the diverse controls between different microbial communities within the same habitat-type, expanding our understanding of temporal dynamics in extreme ecosystems.

text: Temporal dynamics of geothermal microbial communities in Aotearoa-New Zealand Microbial biogeography studies, in particular for geothermal-associated habitats, have focused on spatial patterns and/or individual sites, which have limited ability to describe the dynamics of ecosystem behaviour. Here, we report the first comprehensive temporal study of bacterial and archaeal communities from an extensive range of geothermal features in Aotearoa-New Zealand. One hundred and fifteen water column samples from 31 geothermal ecosystems were taken over a 34-month period to ascertain microbial community stability (control sites), community response to both natural and anthropogenic disturbances in the local environment (disturbed sites) and temporal variation in spring diversity across different pH values (pH 3, 5, 7, 9) all at a similar temperature of 60–70°C (pH sites). Identical methodologies were employed to measure microbial diversity via 16S rRNA gene amplicon sequencing, along with 44 physicochemical parameters from each feature, to ensure confidence in comparing samples across timeframes. Our results indicated temperature and associated groundwater physicochemistry were the most likely parameters to vary stochastically in these geothermal features, with community abundances rather than composition more readily affected by a changing environment. However, variation in pH (pH ±1) had a more significant effect on community structure than temperature (±20°C), with alpha diversity failing to adequately measure temporal microbial disparity in geothermal features outside of circumneutral conditions. While a substantial physicochemical disturbance was required to shift community structures at the phylum level, geothermal ecosystems were resilient at this broad taxonomic rank and returned to a pre-disturbed state if environmental conditions re-established. These findings highlight the diverse controls between different microbial communities within the same habitat-type, expanding our understanding of temporal dynamics in extreme ecosystems.

year: 2023-01-01

title: Te Mata Ono-The six faces of Māori broadcasting

authors: Kaire-Melbourne, Kimiora

subjects: Māori broadcasting

abstract: Māori have always been involved in media communication and from a traditional viewpoint karanga, whaikōrero, taonga pūoro, haka, waiata and mōteatea are all mediums used to share messages across a mass audience. Since the arrival of European settlers, we have seen Māori content disseminated through platforms such as newspaper, radio, and more recently via the medium of television. This particular study is concerned with the way that Māori are represented and information is shared via indigenous broadcaster, Māori Television. Using a theoretical model made up of six key components, this thesis asserts that Te Mata Ono could not only help to improve the production of Māori content but also reshape and modify the medium of television itself, to become more culturally appropriate. Ultimately, this model could guide Māori Television, outlining a Māori specific approach to broadcasting. This study is one part of a two-part study. Due to the limitations of a four-paper masters thesis, I will only be examining three elements of Te Mata Ono, which are Mata Māori, Mata ō-tua and Mata Pākehā. Another thesis that was conducted simultaneously by Te Aorere Pewhairangi explores the remaining three elements of the same model, Mata Iwi, Mata Ako and Mata Tikanga. Te Mata Ono could be applied to Māori Television, making a positive contribution to the future development of Māori broadcasting.

text: Te Mata Ono-The six faces of Māori broadcasting Māori have always been involved in media communication and from a traditional viewpoint karanga, whaikōrero, taonga pūoro, haka, waiata and mōteatea are all mediums used to share messages across a mass audience. Since the arrival of European settlers, we have seen Māori content disseminated through platforms such as newspaper, radio, and more recently via the medium of television. This particular study is concerned with the way that Māori are represented and information is shared via indigenous broadcaster, Māori Television. Using a theoretical model made up of six key components, this thesis asserts that Te Mata Ono could not only help to improve the production of Māori content but also reshape and modify the medium of television itself, to become more culturally appropriate. Ultimately, this model could guide Māori Television, outlining a Māori specific approach to broadcasting. This study is one part of a two-part study. Due to the limitations of a four-paper masters thesis, I will only be examining three elements of Te Mata Ono, which are Mata Māori, Mata ō-tua and Mata Pākehā. Another thesis that was conducted simultaneously by Te Aorere Pewhairangi explores the remaining three elements of the same model, Mata Iwi, Mata Ako and Mata Tikanga. Te Mata Ono could be applied to Māori Television, making a positive contribution to the future development of Māori broadcasting.

year: 2019