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Ribosomes are essential cellular machinery for protein synthesis. It is hypothesised that ribosome content supports muscle growth and that individuals with more ribosomes have greater increases in muscle size following resistance training (RT). Aerobic conditioning (AC) also elicits distinct physiological adaptations; however, no measures of ribosome content following AC have been conducted. We used ribosome‐related gene expression as a proxy measure for ribosome content and hypothesised that AC and RT would increase ribosome‐related gene expression. Fourteen young men and women performed 6 weeks of single‐legged AC followed by 10 weeks of double‐legged RT. Muscle biopsies were taken following AC and following RT in the aerobically conditioned (AC+RT) and unconditioned (RT) legs. No differences in regulatory genes (Ubf, Cyclin D1, Tif‐1a and Polr‐1b) involved in ribosomal biogenesis or ribosomal RNA (45S, 5.8S, 18S and 28S rRNAs) expression were observed following AC and RT, except for c‐Myc (RT > AC+RT) and 5S rRNA (RT < AC+RT at pre‐RT) with 18S external transcribed spacer and 5.8S internal transcribed spacer expression decreasing from pre‐RT to post‐RT in the RT leg only. When divided for change in leg‐lean soft tissue mass (ΔLLSTM) following RT, legs with the greatest ΔLLSTM had lower expression in 11/13 measured ribosome‐related genes before RT and decreased expression in 9/13 genes following RT. These results indicate that AC and RT did not increase ribosome‐related gene expression. Contrary to previous research, the greatest increase in muscle mass was associated with lower changes in ribosome‐related gene expression over the course of the 10‐week training programme. This may point to the importance of translational efficiency rather than translational capacity (i.e. ribosome content) in mediating long‐term exercise‐induced adaptations in skeletal muscle. [ABSTRACT FROM AUTHOR]

Galati, D, Turner, AN, Bishop, C, and Maloney, SJ. Contemporary practices of strength and conditioning coaches in high-level male ice hockey: a survey-based investigation. J Strength Cond Res 37(11): 2241-2250, 2023--The aim of this study was to provide an updated view of the common practices, ideologies, education level, and professional environment of strength and conditioning (S&C) coaches in elite male ice hockey. Nineteen S&C coaches from professional, semiprofessional, and top-tier collegiate hockey teams in North America completed an anonymous online survey. This was composed of 10 sections: (a) background information; (b) technology use, (c) testing and periodization, (d) strength and power, (e) flexibility/mobility, (f) speed, (g) plyometrics, (h) aerobic and anaerobic conditioning, (i) rehabilitation, and (j) challenges and areas of improvement. Fixed-response questions were analyzed through frequency analyses. Thematic analyses were used to identify common themes from open-response questions. Strength and conditioning coaches had an average of 8 (66.5) years of experience when they accepted their current role. The majority held a master's degree and S&C certification. Muscular power, linear speed, and body composition were the most frequently tested qualities. Neuromuscular fatigue was the most important consideration during the season and least important consideration during the off-season. Training frequencies for all physical capacities were lower during the season compared with the off-season. All S&Cs had access to technology, with wearables, with force plates identified as the most used devices. This information may be used by S&C coaches to compare working practices with those used by their peers and inform them of the likely requirements and skill sets needed for job applications. Educational institutions may use this information to align teaching to current practice and to inform future research. [ABSTRACT FROM AUTHOR]

Digby, L, McCarthy, SF, Bornath, DPB, Copeland, JL, and Hazell, TJ. Individual and group responses of cardiorespiratory fitness to running and cycling sprint interval training. J Strength Cond Res 37(4): e313–e316, 2023—Sprint interval training (SIT) has gained popularity as an effective way to improve peak oxygen consumption (V̇O2peak) and subsequently health in a time-efficient manner. In addition, SIT has demonstrated improvements of ∼5–12% in V̇O2peak for both running and cycling protocols, although comparisons of differing modalities have yet to be examined. Therefore, this study sought to determine group and individual responses to running and cycling SIT while examining any crossover effects of running and cycling SIT when V̇O2peak is tested in different modes of exercise where 18 subjects completed either 3 weeks of cycling SIT (6 male, 3 female) or running SIT (5 male, 4 female) consisting of 4–6 repeated 30-second all-out bouts interspersed with 240 seconds of recovery. Cycling and running V̇O2peak tests were completed pretraining and post-training for the investigation of mode-specific cardiorespiratory fitness improvements. There were main effects of time for cycling V̇O2peak (P = 0.022, η p 2 = 0.499) and running V̇O2peak (P = 0.080, η p 2 = 0.334) that seem greater when testing in the same mode as training (∼+5.5%). A similar proportion of responders were identified in both training modes (∼67%) suggesting running and cycling SIT are both effective for improving cardiorespiratory fitness. These results suggest that the specificity of testing and training are important for SIT and that both running and cycling SIT are similarly effective at improving V̇O2peak. [ABSTRACT FROM AUTHOR]

Purpose: We compared the effectiveness of three field-based training programs, namely military-based heat acclimatization (MHA), isothermic conditioning (IC) and interval training (IT), in inducing physiological adaptations in tropical natives. Methods: Fifty-one untrained tropical native males (mean ± standard deviation: age, 25 ± 2 yr; body mass index, 23.6 ± 3.2 kg·m−2; body fat, 19% ± 5%; 2.4-km run time, 13.2 ± 0.9 min) donned the Full Battle Order attire (22 kg) and performed a treadmill route march heat stress test in an environmental chamber (dry bulb temperature, 29.9°C ± 0.5°C; relative humidity, 70% ± 3%). Heat stress tests were conducted before (PRE) and after (POST) a 2-wk training intervention consisting of either a MHA (n = 17, 10 sessions of military-based heat acclimatization), IC (n = 17, 10 sessions with target gastrointestinal temperature (T gi) ≥ 38.5°C) or IT (n = 17, six sessions of high-intensity interval training) program. T gi, HR, mean weighted skin temperature (T sk), physiological strain index (PSI) and thigh-predicted sweat sodium concentration ([Na+]) were measured and analyzed by one-factor and two-factor mixed design ANOVA with a 0.05 level of significance. Results: Field-based IC induced a greater thermal stimulus than MHA (P = 0.029) and IT (P < 0.001) during training. Reductions in mean exercise T gi (−0.2°C [−0.3°C, 0.0°C]; P = 0.009), PSI (−0.4 [−0.7, −0.1]; P = 0.015) and thigh-predicted sweat [Na+] (−9 [−13, −5 mmol·L−1]; P < 0.001) were observed in IC but not MHA and IT (all P > 0.05). Resting HR (MHA, −4 bpm [−7, 0 bpm]; P = 0.025; IC, −7 bpm [−10, −4 bpm]; P < 0.001; IT, −4 bpm [−8, −1 bpm]; P = 0.008) and mean exercise HR (MHA, −4 [−8, 0 bpm]; P = 0.034; IC, −11 bpm [−15, −8 bpm]; P < 0.001, IT = −5 bpm [−9, −1 bpm]; P = 0.012) were lowered in all groups after training. Isothermic conditioning elicited a greater attenuation in mean exercise HR and thigh-predicted sweat [Na+] relative to MHA (both P < 0.05). No between-group differences were observed when comparing MHA and IT (all P > 0.05). Conclusions: Isothermic conditioning induced a more complete heat-adapted phenotype relative to MHA and IT. Interval training may serve as a time efficient alternative to MHA. [ABSTRACT FROM AUTHOR]

Factors influencing inter‐individual variability of responses to resistance training (RT) remain to be fully elucidated. We have proposed the importance of capillarization in skeletal muscle for the satellite cell (SC) response to RT‐induced muscle hypertrophy, and hypothesized that aerobic conditioning (AC) would augment RT‐induced adaptations. Fourteen healthy young (22 ± 2 years) men and women underwent AC via 6 weeks of unilateral cycling followed by 10 weeks of bilateral RT to investigate how AC alters SC content, activity, and muscle hypertrophy following RT. Muscle biopsies were taken at baseline (unilateral), post AC (bilateral), and post RT (bilateral) in the aerobically conditioned (AC + RT) and unconditioned (RT) legs. Immunofluorescence was used to determine muscle capillarization, fiber size, SC content, and activity. Type I and type II fiber cross‐sectional area (CSA) increased following RT, and when legs were analyzed independently, AC + RT increased type I, type II, and mixed‐fiber CSA, where the RT leg tended to increase type II (p =.05), but not type I or mixed‐fiber CSA. SC content, activation, and differentiation increased with RT, where type I total and quiescent SC content was greater in AC + RT compared to the RT leg. Those with the greatest capillary‐to‐fiber perimeter exchange index before RT had the greatest change in CSA following RT and a significant relationship was observed between type II fiber capillarization and the change in type II‐fiber CSA with RT (r = 0.35). This study demonstrates that AC prior to RT can augment RT‐induced muscle adaptions and that these differences are associated with increases in capillarization. [ABSTRACT FROM AUTHOR]

Small-sided games (SSGs) are considered an effective training tool for physical development in soccer. Small-sided games can be modified in several ways to manipulate the physical demands to best match the game demands, player characteristics, and session objectives. The aim of this study was to compare the physiological, perceptual, and Global Positioning System (GPS)--derived time-motion characteristics of man marking (MM) vs. non--man marking (NMM) in 2v2, 3v3, and 4v4 SSGs. In an acute crossover design, 8 amateur soccer players (mean age ± SD: 23.6 ± 3.3 years) played 2v2, 3v3, and 4v4 SSGs consisting of 4 3 4-minute bouts, with 2-minute passive recovery. During all SSGs, players wore a heart rate (HR) monitor and GPS unit and reported their rating of perceived exertion (RPE). Average percent HR (%HRave) induced small to moderate effects with MM compared with NMM (%Δ = 1-2.7%; effect size [ES] = 0.22-0.65). Comparisons between MM formats indicated a decrease in %HRave with increased player numbers (%Δ = 1.6-3.5%; ES = 0.39-0.86). Perceptual load increased with MM compared with NMM (%Δ = 6.7-17.6%; ES = 0.66-2.09), whereas increases in player numbers (MM only) reduced RPE output (%Δ = 9.4-24.3%; ES = 1.14-3.61). Time-motion characteristics revealed substantially greater total distance covered in MM irrespective of player number (%Δ = 6.8-14.7%; ES = 1.34-2.82). There were very likely increases in distances covered at striding (13.1-17.8 km•h-1) (%Δ: 23.4-33.2; ES = 2.42-4.35) and high-intensity running (HIR) (17.9-21 km•h-1) (%Δ: 47.3-104; ES = 0.91-1.68) for MM compared with NMM irrespective of player number. In conclusion, MM substantially elevated perceptual load and distances from striding to HIR regardless of player number, whereas differences between NMM and MM for internal load remain unclear. Use of MM may allow coaches to condition for particularly demanding phases of the game and prescription of larger SSG formats to increase distance covered at higher velocities. [ABSTRACT FROM AUTHOR]

The article presents a study regarding the impacts of kettlebell training on the aerobic capacity of female soccer players of the National Collegiate Athletic Association Division I. It says that the players have completed a graded exercise test to examine their maximum oxygen consumption, and they were assigned to a kettlebell intervention group (KB) or a circuit weight-training (CWT) control group. Results showed that the training has significantly improved aerobic capacity among players.

Background: There is little research exploring training effects of engaging in active video gaming activities.Objectives: This study sought to determine the cardiovascular and metabolic responses, changes in flexibility and exercise adherence to an aerobic dance exercise programme using the XBOX Kinect over a 6 week training period.Methods: Training was conducted using the Just Dance 4 disc on the XBOX Kinect 360. Participants attended five, 30 minute sessions per week for the first two weeks, four 45 minute sessions per week for the next two weeks and three 60 minute sessions per week for the last two weeks. Outcomes assessed included flexibility, body mass index (BMI), percentage body fat, maximal oxygen consumption (VO2max), resting and post exercise blood pressure, heart rate and blood lactate levels.Results: There were significant improvements in flexibility, maximal oxygen consumption and resting heart rate. There were no significant changes in BMI, percentage body fat or blood lactate levels. Nine (37.5%) participants continued to engage in this form of exercise at least 3-days per week over the 3-month post intervention follow-up period.Conclusion: Engaging in dancing using dance videogames can lead to improved cardiovascular conditioning and flexibility in sedentary female university students. [ABSTRACT FROM AUTHOR]

Objective. This pilot study was designed to evaluate the impact of a home-based aerobic conditioning program on symptoms of fibromyalgia and determine if changes in symptoms were related to quantitative changes in aerobic conditioning (VO2 max). Methods. Twenty-six sedentary individuals diagnosed with fibromyalgia syndrome participated in an individualized 12-week home-based aerobic exercise program with the goal of daily aerobic exercise of 30 minutes at 80% of estimated maximum heart rate. The aerobic conditioning took place in the participants' homes, outdoors, or at local fitness clubs at the discretion of the individual under the supervision of a physical therapist. Patients were evaluated at baseline and completion for physiological level of aerobic conditioning (VO2 max), pain ratings, pain disability, depression, and stress. Results. In this pilot study subjects who successfully completed the 12-week exercise program demonstrated an increase in aerobic conditioning, a trend toward decrease in pain measured by the McGill Pain Questionnaire-Short Form and a weak trend toward improvements in visual analog scale, depression, and perceived stress. Patients who were unable or unwilling to complete this aerobic conditioning program reported significantly greater pain and perceived disability (and a trend toward more depression) at baseline than those who completed the program. Conclusions. Patients suffering from fibromyalgia who can participate in an aerobic conditioning program may experience physiological and psychological benefits, perhaps with improvement in symptoms of fibromyalgia, specifically pain ratings. More definitive trials are needed, and this pilot demonstrates the feasibility of the quantitative VO2 max method. Subjects who experience significant perceived disability and negative affective symptoms are not likely to maintain a home-based conditioning program, and may need a more comprehensive interdisciplinary program offering greater psychological and social support. [ABSTRACT FROM AUTHOR]

The article reports on research conducted to investigate and compare the effect kettlebell swings and treadmill running had on the perceived exertion values and metabolic demand of male and female subjects. Researchers evaluated 11 male and two female subjects. They found that average heart rate and perceived exertion values did not differ between kettlebell and treadmill subjects. They also found that treadmill running resulted in higher oxygen consumption and more calories being burned.

Aerobic conditioning (AC) performed either during or after sensitization reduces allergic inflammation in mice; however, the effects of AC performed before and during allergic sensitization on airway inflammation are unknown. Mice were divided into Control, AC, OVA, and AC + OVA groups. Mice were trained in a treadmill followed by either ovalbumin (OVA) sensitization or saline administration. Peribronchial inflammation, OVA-specific IgE and IgG1 titers, the expression of Th1 and Th2 cytokines, and airway remodeling were evaluated, as well as the expression of Eotaxin, RANTES, ICAM-1, VCAM-1, TGF-β and VEGF. Aerobic conditioning performed before and during allergic sensitization displayed an inhibitory effect on the OVA-induced migration of eosinophils and lymphocytes to the airways, a reduction of IgE and IgG1 titers and an inhibition of the expression of Th2 cytokines. The AC + OVA group also demonstrated reduced expression of ICAM-1, VCAM-1, RANTES, TGF-β and VEGF, as well as decreased airway remodeling (p < 0.05). The effects of AC before and during the sensitization process inhibit allergic airway inflammation and reduce the production of Th2 cytokines and allergen-specific IgE and IgG1. [ABSTRACT FROM AUTHOR]

Background: Implantable cardioverter defibrillators (ICDs) are an increasingly common treatment for survivors of sudden cardiac arrest or others with life-threatening ventricular arrhythmias. Health-care providers are often reluctant to prescribe exercise for this group because of the belief that it will provoke ventricular arrhythmias and cardiac arrest; patients are often afraid to exercise because of concern over receiving an ICD shock. A social cognitive theory-driven exercise intervention aimed at stabilizing cardiac arrhythmias and reducing ICD shocks by increasing parasympathetic autonomic nervous system control is described. Methods: The exercise intervention has two phases that include an 8-week aerobic conditioning component followed by a 16-week exercise maintenance component. The aerobic exercise intervention is expected to have significant impact on cardiopulmonary function, ventricular arrhythmias, cardiac autonomic function, and self-efficacy in persons who have an ICD. The exercise intervention is currently being tested using a randomized clinical trial format, the results of which will be available in 2012. Conclusion: The exercise after ICD trial is one of the first clinical trials to test the effects of aerobic exercise on cardiopulmonary outcomes after receiving an ICD for primary or secondary prevention of sudden cardiac arrest. (PACE 2010; 973–980) [ABSTRACT FROM AUTHOR]

The article reports on research conducted to investigate the influences player number and playing area size had on the heart rate responses elicited by junior male rugby league players during small sided games. Researchers evaluated 22 players from a professional rugby club. They found that playing area size did not lead to changes in heart rate but that player number did.

Background and Purpose. This case report describes a fitness program for children with disabilities and provides preliminary information about the safety and feasibility of the program. Case Description. Nine children, 5 to 9 years of age with physical or other developmental disabilities, participated in a 14-week group exercise program held 2 times per week followed by a 12-week home exercise program. Energy expenditure index, leg strength (force-generating capacity of muscle), functional skills, fitness, self-perception, and safety were measured before intervention, after the group exercise program, and again after the home exercise program. Outcomes. No injuries occurred, and improvements in many of the outcome measures were observed. More improvements were observed after the group exercise program than after the home program, and adherence was better during the group exercise program. Discussion. This case report demonstrates that a group exercise program of strength and endurance training may be a safe and feasible option for children with disabilities. Further research is needed to evaluate the effectiveness of a group fitness program and optimal training parameters. [ABSTRACT FROM AUTHOR]