High Intensity Functional Training (HIFT) Improves Fitness in Recruit Firefighters

Background: Firefighting is a strenuous profession requiring adequate levels of fitness for effective job performance. Providing firefighters with a safe and effective fitness program is essential for optimal performance. The purpose of this project was to examine changes in various parameters of physical fitness and firefighter ability following a 7-week high intensity functional training (HIFT) program. Methods: Participants were male firefighter recruits (N = 89; age = 27.1 ± 4.2 years, height = 1.78 ± 0.1 m, BMI = 28.1 ± 4.2) enrolled in a Basic Operations Firefighter Academy. Fitness and firefighting ability (via the Academy Firefighter Challenge) were assessed at Weeks 1 and 7 of the Academy. Results: Significant improvements in both fitness and firefighter ability were seen following the HIFT program. Specifically, fitness (BMI, cardiovascular fitness, muscular endurance) improved significantly [Hotelling’s T2 = 8.98, F(5, 84) = 150.92, p < 0.001, η2p = 0.90]. Firefighter ability also improved significantly [Hotelling’s T2 = 3.95, F(7, 88) = 46.26, p < 0.001, η2p = 0.80]. Conclusions: Following a 7-week Basic Operations Firefighter Academy that included daily HIFT, significant increases in fitness and firefighting ability were observed. These findings suggest that HIFT appears to be an effective means of improving fitness and firefighting ability in recruit firefighters.

AN APPLICATION OF HOTELLING’S T2 TEST FOR THE COMPARISON OF THE VISUAL-ACOUSTIC METHOD IN THE IDENTIFICATION OF INGESTIVE CATTLE BEHAVIOR

The bioacoustic method is an important tool for the identification of the ingestive behavior of ruminants, especially in extensive production systems. This is mainly due to its potential to solve the deficiencies presented by the usual method, which is based on the visual observation of the animals. In this article, we present a study whose main objective is to evaluate the accuracy of the bioacoustic method over the visual method to record the macroactivity of grazing cattle ingestive behavior. The comparison of the methods is made in terms of a multivariate statistical approach based on the use of Hotelling’s T2 test. To verify the test performance in comparing the methods, we developed a simulation study using a resampling approach. The results show that the bioacoustic method can be an effective alternative to the visual method, with the advantage of being a noninvasive method that also allows the analysis of the micro events of ingestive behavior.

ANALISIS MULTIVARIAT (UJI HOTELLING’S T2)

Salah satu uji statistik multivariat yang sering digunakan adalah Uji Hotelling’s T2. Uji Hotelling’s T2 (Hotelling, 1931) berfungsi untuk melihat perbedaan antara dua kelompok percobaan, yang masing-masing kelompok terdiri dari dua variate atau lebih, dan akan dilakukan analisis statistik pada variate tersebut secara serentak1. Uji Hotelling’s T2 atau statistik T2 pada dua sampel bebas adalah salah satu teknik analisis statistik komparasional multivariat yang digunakan untuk membandingkan dua kelompok sampel yang diteliti. Uji Hotelling’s T2 merupakan statistik multivariat yang menjadi pengembangan uji T dua sampel bebas (Perbedaan mean dua kelompok yang bersifat independen). Perbedaannya terletak pada jumlah variabel dependen. Pada Uji T dua sampel bebas hanya memiliki satu variabel dependen, sedangkan uji Hotelling’s T2 memiliki lebih dari satu variabel dependen2.

Methods of comparison of surface texture based on fractal dimension and Hotelling’s T2 test

Comparative analysis of the surface texture of machine parts can be successfully carried out using statistical tests. The paper presents a methodology of method used to compare the surface texture by applying Hotelling’s T2 test as well as a method used to evaluate surface topography by applying fractal dimension. The tests were carried out on samples produced with the use of face milling process for four types of materials. The following types of steel were used: 40HM, C45, NC6 and WCL. For each type of material, four areas were machined with the same machining parameters. Based on these results a decision was made whether the surfaces, despite the same machining conditions, were significantly different from each other. Furthermore, the analysis indicated that the fractal dimension enabled to characterise signal irregularities in quantitative and qualitative way.