0000000000069944

AUTHOR

Jani P. Vaara

Neuromuscular Performance and Hormonal Profile During Military Training and Subsequent Recovery Period

Introduction Military training loads may induce different physiological responses in garrison and field training and only a little is known about how short-time recovery, lasting a few days, affects neuromuscular fitness and hormonal profile. This study aimed to investigate the effects of garrison and field military service on neuromuscular performance and hormonal profile and to evaluate the effects of a 3-day recovery on those factors. Methods Twenty healthy male soldiers (20 ± 1 years) participated in the study, which consisted of 4 days of garrison training [days (D) 1–4] and 7 days of military field training (Days 5–12) followed by a 3-day recovery period (Day 15). Serum hormone concen…

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Effects of overnight military training and acute battle stress on the cognitive performance of soldiers in simulated urban combat

Understanding the effect of stress, fatigue, and sleep deprivation on the ability to maintain an alert and attentive state in an ecologically valid setting is of importance as lapsing attention can, in many safety-critical professions, have devastating consequences. Here we studied the effect of close-quarters battle (CQ battle) exercise combined with overnight military training with sleep deprivation on cognitive performance, namely sustained attention and response inhibition. In addition, the effect of the CQ battle and overnight training on cardiac activity [heart rate and root mean square of the successive differences (RMSSD)] during the cognitive testing and the relationship between ca…

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Can Physiological and Psychological Factors Predict Dropout from Intense 10-Day Winter Military Survival Training?

Background: In the military context, high levels of physiological and psychological stress together can compromise individual&rsquo

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Accelerometer-Based Sedentary Time, Physical Activity, and Serum Metabolome in Young Men

Physical activity (PA) has been shown to associate with many health benefits but studies with metabolome-wide associations with PA are still lacking. Metabolome studies may deepen the mechanistic understanding of PA on the metabolic pathways related to health outcomes. The aim of the present study was to study the association of accelerometer based sedentary time (SB) and PA with metabolome measures. SB and PA were measured by a hip-worn accelerometer in 314 young adult men (age: mean 28, standard deviation 7 years). Metabolome was analyzed from fasting serum samples consisting of 66 metabolome measures (nuclear magnetic resonance-based metabolomics). The associations were analyzed using a …

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Maximal Strength, Muscular Endurance and Inflammatory Biomarkers in Young Adult Men

The aim was to study associations of maximal strength and muscular endurance with inflammatory biomarkers independent of cardiorespiratory fitness in those with and without abdominal obesity. 686 young healthy men participated (25±5 years). Maximal strength was measured via isometric testing using dynamo-meters to determine maximal strength index. Muscular endurance index consisted of push-ups, sit-ups and repeated squats. An indirect cycle ergometer test until exhaustion was used to estimate maximal aerobic capacity (VO2max). Participants were stratified according to those with (102 cm) and those without abdominal obesity (102 cm) based on waist circumference. Inflammatory factors (C-react…

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Device-Based Measures of Sedentary Time and Physical Activity Are Associated With Physical Fitness and Body Fat Content

Introduction/Purpose: Physical activity and sedentary time may associate with physical fitness and body composition. Yet, there exists some observational studies that have investigated the associations of device-based measures of sedentary time and physical activity (PA) with cardiorespiratory fitness (CRF) and body composition but associations with muscular fitness (MF) are less studied.Methods: Objective sedentary time and physical activity was measured by a hip worn accelerometer from 415 young adult men (age: mean 26, standard deviation 7 years). Cardiorespiratory fitness (VO2max) (CRF) was determined using a graded cycle ergometer test until exhaustion. Maximal force of lower extremiti…

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Muscular and cardiorespiratory fitness are associated with health-related quality of life among young adult men

Abstract Background Despite numerous studies providing evidence for positive effects of physical activity and physical fitness, evidence for association between physical fitness and health-related quality of life (HRQoL) in young adults is limited. The aim of the present cross-sectional study was to investigate the association of cardiorespiratory and muscular fitness with HRQoL from the perspective of its physical and mental components among young adult Finnish males. Methods The sample consisted of 754 men, with the mean age of 26 years (SD 6.7 years), who participated in the military refresher training. HRQoL was measured using the Finnish RAND 36-item health survey. Cardiorespiratory fi…

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Associations of leisure time, commuting and occupational physical activity with fitness and clustered cardiovascular risk factor

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Cycling but not walking to work or study is associated with physical fitness, body composition and clustered cardiometabolic risk in young men

IntroductionActive commuting is an inexpensive and accessible form of physical activity and may be beneficial to health. The aim of this study was to investigate the association of active commuting and its subcomponents, cycling and walking, with cardiometabolic risk factors, physical fitness and body composition in young men.MethodsParticipants were 776 Finnish young (26±7 years), healthy adult men. Active commuting was measured with self-report. Waist circumference was measured and body mass index (BMI) calculated. Aerobic fitness was measured with bicycle ergometer and muscular fitness with maximal leg and bench press, sit-ups, push-ups and standing long jump. Cardiometabolic risk factor…

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Physical training considerations for optimizing performance in essential military tasks

Physically demanding essential military tasks include load carriage, manual material handling and casualty evacuation. This narrative review characterizes the main physical attributes related to performance of these occupational tasks and reviews physical training intervention studies in military settings to improve performance in these military tasks. Load carriage performance requires both aerobic and neuromuscular fitness with greater emphasis on maximal strength and absolute maximal oxygen uptake, especially when carrying heavier loads. In manual material handling, maximal strength and power are strongly associated with discrete lifting, while muscular strength, muscular endurance and a…

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Childhood Sports Participation Is Associated With Health-Related Quality of Life in Young Men: A Retrospective Cross-Sectional Study

The aim of the study was to examine whether sports participation (SP), engagement in competitive sports (CS) and the type of sport undertaken at the age of 12 are associated with the physical and the mental components of health-related quality of life (HRQoL) in young adulthood. The data were collected using questionnaires prior to a compulsory military refresher training course in Finland. The sample consisted of 784 men (mean age 26 years). HRQoL was measured with RAND 36 and childhood sports participation with a series of questions. Data were analysed with logistic regression. Higher frequency of SP, participation in district level CS, performing team, endurance or extreme sports and pla…

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60-Hour Sleep Deprivation Affects Submaximal but Not Maximal Physical Performance

The effect of 60-h sleep deprivation (SD) on physical performance and motor control was studied. Twenty cadets were measured for aerobic performance (VO2) before and immediately after the SD period. Maximal strength and EMG of the knee extensor muscles were measured before and after 60 h of SD. Balance, reaction times and motor control were assessed every evening and morning during the SD period. Main effects were observed for heart rate (p = 0.002, partial eta squared: 0.669), VO2 (p = 0.004, partial eta squared: 0.621), ventilation (p = 0.016, partial eta squared: 0.049), and lactate concentration (p = 0.022, partial eta squared: 0.501), whereas RER remained unaltered (p = 0.213, partial …

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Associations of Aerobic Fitness and Maximal Muscular Strength With Metabolites in Young Men

This cross-sectional study of young Finnish men examines the associations of aerobic fitness and muscular strength with metabolome measures that are associated with cardiometabolic risks.

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Relationships between leisure time physical activity, physical fitness and mental health among young adult males

Physical activity has been seen as an important tool to prevent both physical and mental disorders like depression and anxiety. However, previous research has mainly focused on mental health problems rather than positive mental health. The aim of the present study was to investigate the association of leisure time physical activity (LTPA) and physical fitness with mental distress and positive mental health. The study sample consisted of 792 men (mean age 26 years) who participated in the study prior their military refresher-training course. Cardio-respiratory and muscle fitness tests were measured, and LTPA, positive mental health (Warwick–Edinburgh Mental Wellbeing Scale, SWEMWBS) and ment…

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Device-Based Measures of Sedentary Time and Physical Activity Are Associated With Physical Fitness and Body Fat Content

Introduction/Purpose: Physical activity and sedentary time may associate with physical fitness and body composition. Yet, there exists some observational studies that have investigated the associations of device-based measures of sedentary time and physical activity (PA) with cardiorespiratory fitness (CRF) and body composition but associations with muscular fitness (MF) are less studied. Methods: Objective sedentary time and physical activity was measured by a hip worn accelerometer from 415 young adult men (age: mean 26, standard deviation 7 years). Cardiorespiratory fitness (VO2max) (CRF) was determined using a graded cycle ergometer test until exhaustion. Maximal force of lower extremit…

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Energy Balance, Hormonal Status, and Military Performance in Strenuous Winter Training

Severe energy deficit may impair hormonal regulation and physical performance in military trainings. The aim of this study was to examine the associations between energy intake, expenditure, and balance, hormones and military performance during a winter survival training. Two groups were studied: the FEX group (n = 46) had 8-day garrison and field training, whereas the RECO group (n = 26) had a 36-h recovery period after the 6-day garrison and field training phase. Energy intake was assessed by food diaries, expenditure via heart rate variability, body composition by bioimpedance, and hormones by blood samples. Strength, endurance and shooting tests were done for evaluating military perform…

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Performance changes during repeated military occupational test and its associations to physical performance

The present study investigated performance changes during three runs (1 min recovery) of repeated military simulation task test (RMST) and its associations with physical performance. Voluntary male soldiers (N = 114) participated in a series of measurements of physical performance. Lower body explosive force production, anaerobic endurance and upper body strength endurance together explained 58% of the variance in the first RSMT (p < 0.001). The same variables explained the variance in the second and third runs of RSMT by 60% and 51%, but explosive force production was replaced with aerobic endurance, assessed by the 3.2 km loaded run (p < 0.001). This study demonstrated that the role of ex…

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Cardiorespiratory and muscular fitness in young adult Finnish men between 2003 and 2015

Introduction Physical fitness is strongly related to health and may offer valuable information about public health. We investigated trends in physical fitness, leisure-time physical activity (LTPA), and anthropometry of young healthy adult Finnish men in representative population-based samples between 2003 and 2015. Methods Three independent cross-sectional samples of 18- to 35-year-old Finnish men were assessed in 2003 (n = 889), 2008 (n = 803), and 2015 (n = 690). Cardiorespiratory (VO(2)max) and muscular fitness (1-minute sit-ups and push-ups), body mass, and height were measured. Self-reported LTPA was assessed. Results After adjusting for age, education, and smoking, cardiorespiratory …

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Associations of serum 25(OH)D levels with physical performance and anabolic hormones in young men

Purpose: The present study examined the association of vitamin D measured by serum 25(OH)D with physical performance outcomes and serum levels of anabolic hormones in young men.Methods: 412 young men (age 19 ± 1 year) entering their compulsory military service volunteered to participate in the study. The study consisted of two groups from two different military bases: Group A was studied in January and group B in July. The groups were first compared with each other and due to statistically significant (p &amp;lt; 0.001 analyzed with independent samples t-test) differences in physical condition (sit-up, push-up, and standing long jump-tests and testosterone levels) between the groups, groups…

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High-Intensity Functional Training Induces Superior Training Adaptations Compared With Traditional Military Physical Training

Helén, J, Kyröläinen, H, Ojanen, T, Pihlainen, K, Santtila, M, Heikkinen, R, and Vaara, JP. High-intensity functional training induces superior training adaptations compared with traditional military physical training. J Strength Cond Res XX(X): 000–000, 2023—This study examined the effectiveness of concurrent strength and endurance training with an emphasis on high-intensity functional training (HIFT) during military service. Voluntary male conscripts (aged 18–28 years) were placed in either an experimental (EXP: n = 50–66) or a control (CON: n = 50–67) group. The training for the EXP group included HIFT using body mass, sandbags, and kettlebells. The CON group trained according to the cur…

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Muscular Fitness Improves during the First Year of Academy Studies among Fighter Pilot Cadets

Background: An adequate level of muscular fitness is related to occupational performance in military personnel, including pilots flying high performance aircraft. The aim of this study was to describe the baseline level and the change in muscular fitness between the first and the second years of the Air Force Academy among fighter pilot cadets. Methods: The muscular strength and endurance test results of 182 male fighter pilot cadets were analyzed during their first year in the Air Force Academy and one year after. Maximal isometric strength tests included trunk flexion, trunk extension and bilateral leg extension tests, whereas muscle endurance was measured with modified a sit-up test and …

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Relationship Between Accelerometer-Based Physical Activity, Sedentary Behavior, and Mental Health in Young Finnish Men

Healthy lifestyle behaviors including physical activity (PA) have been recognized to contribute positively to mental health. Most of the evidence on relationship between PA and mental health relies on self-reported PA results. Device-based measures on PA or sedentary behavior (SB) are less frequently used in mental health research. The present study aimed at examining the relationship between mental health and PA/SB measured by accelerometers in young Finnish men. The sample consisted of 409 men (mean age 28 ± 7 years), who participated in the military refresher training in Finland. Self-rated mental health was measured with Mental Health Inventory (MHI-5) and short Warwick-Edinburgh Mental…

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Physical training considerations for optimizing performance in essential military tasks.

Physically demanding essential military tasks include load carriage, manual material handling and casualty evacuation. This narrative review characterizes the main physical attributes related to performance of these occupational tasks and reviews physical training intervention studies in military settings to improve performance in these military tasks. Load carriage performance requires both aerobic and neuromuscular fitness with greater emphasis on maximal strength and absolute maximal oxygen uptake, especially when carrying heavier loads. In manual material handling, maximal strength and power are strongly associated with discrete lifting, while muscular strength, muscular endurance and a…

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Relationship between different domains of physical activity and positive mental health among young adult men

Abstract Background There is growing evidence on positive effects of physical activity (PA) on mental health. However, the focus of previous research on this relationship has typically been on mental health from the perspective of mental health problems rather than from the perspective of mental wellbeing. Further, previous research has commonly focused rather on leisure time PA without evidence on the role of other domains of PA. The aim of the present cross-sectional study was to investigate the relationship between positive mental health (PMH) and different domains of PA in young Finnish men. The secondary aim was to examine the reasons for physical inactivity among individuals with a lo…

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Relationships between psychosocial well-being and leisure time physical activity among 160.000 young Finnish men: a cross-sectional study during 2015–2021

AbstractEvidence on the relationship between psychosocial well-being and physical activity (PA) is insufficient, especially in young adults between 18 and 29 years. Identifying protective factors for psychosocial well-being as well as factors that may promote PA behaviour in this specific age group is crucial.The aim of the present study was to explore the association between self-reported leisure time physical activity (LTPA) and a number of measures of psychosocial well-being in a large sample of Finnish young men. The sample used for this study is based on registers of the Finnish Defence Forces and consist of questionnaire-based data collected from 159,776 young healthy men (18–29 years…

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Effects of baseline fitness and BMI levels on changes in physical fitness during military service.

Objectives The purpose of the present study was to investigate how aerobic fitness, muscle fitness and body mass index (BMI) change in relation to their baseline levels during 6-12 months of military service. Design Retrospective longitudinal follow-up study. Methods The study group consisted of 249 279 healthy young male conscripts (age 19.1 ± 0.4 yrs.) who completed their military service between the years 2005-2015. Anthropometrics (body mass, height, BMI), aerobic fitness (12-minute running test) and muscle fitness (sit-ups, push-ups, standing long jump) were measured. Results A 12-minute running test improved by 5% (107 ± 292 m), standing long jump 1% (2.1 ± 16.2 cm), 1-min sit-ups 19%…

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Association between spinal disorders and different domains of physical activity among young adult men

BackgroundThere is limited evidence of how physical activity (PA) associates with low back pain (LBP) and neck pain (NP). Particularly, the association between occupational or commuting PA and LBP/NP is unclear. The aim of the present cross-sectional study was to investigate the association between spinal disorders and different physical activity domains in young and healthy adult men.MethodsSelf-reported leisure time, occupational and commuting PA, as well as LBP and NP, were studied using questionnaires among young Finnish males (n = 1,630). Logistic regression analysis was used to study the associations of PA domains, physical fitness, and spinal disorders. Regression models were adjuste…

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Associations of Maximal Strength and Muscular Endurance with Cardiovascular Risk Factors

The aim was to study the associations of maximal strength and muscular endurance with single and clustered cardiovascular risk factors. Muscular endurance, maximal strength, cardiorespiratory fitness and waist circumference were measured in 686 young men (25±5 years). Cardiovascular risk factors (plasma glucose, serum high- and low-density lipoprotein cholesterol, triglycerides, blood pressure) were determined. The risk factors were transformed to z-scores and the mean of values formed clustered cardiovascular risk factor. Muscular endurance was inversely associated with triglycerides, s-LDL-cholesterol, glucose and blood pressure (β=-0.09 to - 0.23, p0.05), and positively with s-HDL choles…

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Relationships Between Youth Sports Participation and Mental Health in Young Adulthood Among Finnish Males

Purpose: To examine whether retrospectively assessed sports participation (SP) and competitive sports (CS) at the age of 12 years is associated with mental health and health behavior in young adulthood among males. Design: A cross-sectional study using self-administered questionnaires. Setting: Conducted prior to compulsory military refresher training course in Finland allowing geographically representative sample of Finnish young men. Participants: Six hundred eighty males aged between 20 and 35 years. Measures: Mental well-being was measured with the short version of Warwick-Edinburgh Mental Well-Being Scale and mental distress with 5 items of The Short Form Helalth Survey (SF-36) scale. …

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Effects of Added Resistance Training on Physical Fitness, Body Composition, and Serum Hormone Concentrations During Eight Weeks of Special Military Training Period

A high volume of military training has been shown to compromise muscle strength development. We examined effects of added low-volume resistance training during special military training (ST) period, which took place after basic training period. Male conscripts (n = 25) were assigned to standardized ST with added resistance training group (TG, n = 13) and group with standardized ST only (control) (CG, n = 12). Standardized ST with added resistance training group performed 2 resistance training sessions per week for 8 weeks: hypertrophic strength (weeks 1-3), maximal strength (weeks 4-6) and power training (weeks 7-8). Maximal strength tests, load carriage performance (3.2 km, 27 kg), and hor…

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Optimising training adaptations and performance in military environment.

Abstract Objectives Worldwide decreases in physical fitness and increases in body fat among youth have set challenges for armed forces to recruit physically capable soldiers. Therefore, knowledge of optimizing physical adaptation and performance through physical training is vital. In addition, maintaining or improving physical performance among professional soldiers in various military environments is crucial for overall military readiness. The present review focuses on the effects of military training on physical performance by searching for optimal methods to do it. Design and methods Review article based on selected literature searches using the main keywords ‘physical performance’ and ‘…

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Physiological and physical performance changes during a 20-day winter military training course and its subsequent 10-day recovery period

The present study investigated physiological, mental and physical performance changes during a 20-day winter military training course and the following 10-day recovery period. Fifty-eight (age 19 ± 1 years, height 182 ± 6 cm, body mass 78.5 ± 7.2 kg) male soldiers volunteered. Body composition, serum biomarker levels and performance tests were measured four times during the study. In addition, questionnaires were collected daily for subjective stress and rate of perceived exertion. The course induced significant declines in body (−3.9%, p < 0.05) and fat mass (−31.6%, p < 0.05) as well as in all assessed physical performance variables (−9.2 - −20.2%, p < 0.05), testosterone (−73.7%, p < 0.0…

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Optimising Training Adaptations and Performance in Military Environment

Abstract Objectives Worldwide decreases in physical fitness and increases in body fat among youth have set challenges for armed forces to recruit physically capable soldiers. Therefore, knowledge of optimizing physical adaptation and performance through physical training is vital. In addition, maintaining or improving physical performance among professional soldiers in various military environments is crucial for overall military readiness. The present review focuses on the effects of military training on physical performance by searching for optimal methods to do it. Design and methods Review article based on selected literature searches using the main keywords ‘physical performance’ and ‘…

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Elevated concentration of oxidized LDL together with poor cardiorespiratory and abdominal muscle fitness predicts metabolic syndrome in young men

Metabolic syndrome (MetS) is associated with increased oxidized LDL (ox-LDL), systemic inflammation, and poor cardiorespiratory fitness. We examined affiliations of these factors and the effect of muscular fitness on MetS in young healthy men.Physical fitness, ox-LDL, tumor necrosis factor α (TNFα), interleukin-6 (IL-6) and serum lipids were measured in a nationally representative sample of Finnish young men with and without MetS. Participants (mean age 25.1years) performed tests of maximal oxygen uptake (VO₂max) and muscle fitness, and were divided into MetS (n=54, IDF 2007 criteria) and non-MetS (n=790). Age, smoking and leisure-time physical activity were used as covariates (ANCOVA).The …

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Cardiorespiratory and Muscular Fitness are Associated with Cardiovascular Risk Related to Obesity in Young Men

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Training-Induced Acute Neuromuscular Responses to Military Specific Test during a Six-Month Military Operation

Limited data are available regarding strength and endurance training adaptations to occupational physical performance during deployment. This study assessed acute training-induced changes in neuromuscular (electromyography

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Physical Fitness and Hormonal Profile During an 11-Week Paratroop Training Period.

Physical fitness and serum hormone concentrations have been shown to change during military training. The purpose was to examine these chronic changes in paratroopers (n = 52 male conscripts) during an 11-week training period, including acute changes induced by strenuous 5-day military field training. Hormonal profiles, body mass, maximal strength, muscle endurance, and 12-minute running test were assessed at several time points during paratrooper training. In the latter part of the training period, conscripts were involved in strenuous military field training (5 days). At week 7, during specialized military training period, aerobic performance decreased (3,146 ± 163 m) but recovered back t…

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