Changes in Body Composition and Strength after 12 Weeks of High-Intensity Functional Training with Two Different Loads in Physically Active Men and Women: A Randomized Controlled Study

This study examined the effects of two different resistance loads during high-intensity Functional Training (HIFT) on body composition and maximal strength. Thirty-one healthy young individuals were randomly assigned into three groups: moderate load (ML: 70% 1-RM), low load-(LL: 30% 1-RM), and control (CON). Each experimental group performed HIFT three times per week for 12 weeks with a similar total volume load. Body fat decreased equally in both experimental groups after 6 weeks of training (p < 0.001), but at the end of training it further decreased only in LL compared to ML (−3.19 ± 1.59 vs. −1.64 ± 1.44 kg, p < 0.001), with no change in CON (0.29 ± 1.08 kg, p = 0.998). Lean body mass (LBM) increased after 6 weeks of training (p = 0.019) in ML only, while after 12 weeks a similar increase was observed in LL and ML (1.11 ± 0.65 vs. ML: 1.25 ± 1.59 kg, p = 0.034 and 0.013, respectively), with no change in CON (0.34 ± 0.67 kg, p = 0.991). Maximal strength increased similarly in four out of five exercises for both experimental groups by between 9.5% and 16.9% (p < 0.01) at the end of training, with no change in CON (−0.6 to 4.9%, p > 0.465). In conclusion, twelve weeks of HIFT training with either low or moderate resistance and equal volume load resulted in an equal increase in LBM and maximal strength, but different fat loss.

High-intensity resistance exercise is not as effective as traditional high-intensity interval exercise for increasing the cardiorespiratory response and energy expenditure in recreationally active subjects

Purpose Traditional high-intensity interval exercise (HIIE) highly stimulates the cardiorespiratory system and increases energy expenditure (EE) during exercise. High-intensity resistance exercise (HIRE) has become more popular in recreationally active subjects. The physiological responses to HIRE performed with light or moderate load is currently largely unknown. Here, we examined the effect of the type of interval exercise [HIRE at 40% (HIRE40) and 60% (HIRE60) 1-RM vs. traditional HIIE] on the cardiorespiratory response and EE during and after exercise. Methods Fifteen recreationally active adults randomly completed traditional HIIE on an ergocyle, HIRE40 and HIRE60. The sessions consisted of two sets of ten 30-s intervals (power at 100% VO2max during HIIE; maximal number of repetitions for 10 different free-weight exercises during HIRE40 and HIRE60) separated by 30-s active recovery periods. Gas exchange, heart rate (HR) and EE were assessed during and after exercise. Results VO2mean, VO2peak, HRmean, the time spent above 90% VO2max and HRmax, and aerobic EE were lower in both HIRE sessions compared with HIIE (P < 0.05). Anaerobic glycolytic contribution to total exercise EE was higher in HIRE40 and HIRE60 compared with HIIE (P < 0.001). EE from excess post-exercise oxygen consumption (EPOC) was similar after the three sessions. Overall, similar cardiorespiratory responses and EE were found in HIRE40 and HIRE60. Conclusions HIRE is not as effective as HIIE for increasing the cardiorespiratory response and EE during exercise, while EPOC remains similar in HIRE and HIIE. These parameters are not substantially different between HIRE40 and HIRE60.

Stress as a Workload in Intensive Care Units

Stress is one of the significant workloads in intensive care units. This survey examines the relationship between the level of stress experienced, gender, age, length of practice and the degree of the workplace. It maps the factors that lead to the emergence of stress in intensive care units and examines its impact on work performance. Results from 121 respondents working in intensive care units show that the level of stress correlates with age and is typical for certain stages of life. Work stress is mostly created by load, where the physical and mental component is applied. Total physical activity corresponded to moderate load and the most important physical factors represented increased demands on the musculoskeletal system and disturbance of sleep rhythm. The level of mental stress was also in the moderate values. The most important psychologicalstressors were identified as a high degree of responsibility and increased demands on cognitive functions

Mechanism of Fracture in Pre-Cracked Single-Edged Notched Bars With AI2O3-TiO2 and WC-CO Coatings

Experimental analysis is made to investigate the most significant fracture characterizing parameters in plasma sprayed substrate-coating composite. The experiments were conducted on the single edge notched bars (SENB) made with 7075 series aluminum alloy, with plasma sprayed Al2O3-TiO2 and WC-Co top coats. The pre-cracked bars were fractured in computerized universal testing machine in controlled conditions. The material has been tested under age-hardened and coated conditions also. The results have revealed that the age hardening and type of coating have a much influence on strain energy release rate. The experimental results have shown that WC-Co coated normal materials possess higher strength whereas uncoated normal materials possess lower strength. It is also found that Al2O3-TiO2 coated material possess better coating bond strength and moderate load bearing capacity. The SEM fractographic analysis has been made to analyze the fracture behavior as a function of coating type and the material conditions.

Women with Fibromyalgia Prefer Resistance Exercise with Heavy Loads—A Randomized Crossover Pilot Study

Fibromyalgia (FM) is a chronic pain condition associated with impaired muscle strength and exercise-induced pain. Physical exercise has been highlighted, by international clinical guidelines and stakeholders, as an essential component of rehabilitation in FM. Exposure to pain during exercise is generally correlated with elevated lactate levels and, additionally, is one known reason for persons with FM to avoid physical exercise and activity. A crossover design was used to test and evaluate an approach consisting of resistance exercise with heavy loads and a low number of repetitions among ten women with FM. The participants were consecutively recruited to test and perform exercise with two different resistance levels (A = light/moderate load, and B = heavy load) in a randomized crossover trial using an AB/BA setting. Results showed that the heavy load exercise session was experienced as more positive than the light/moderate load exercise session and that lower lactate levels followed exercise with heavier weight loads. This is promising and indicates that the approach of heavy weight loads and accustomed repetitions is accepted in FM and has the potential to attenuate hesitation to exercise due to exercise-induced pain. However, these effects need to be further investigated in more extensive studies.

Assessment of Heavy Metal Contents in Three Different Land used Soils in Ohaji/Egbema Imo State, Nigeria

This assessment of some heavy metal contents in different land used soils in Ohaji/Egbema, Imo State was conducted between June, 2019 and May, 2020. Three land used soils namely; the grass land, continuously cropped and forest land were studied. Soil profile representations were established in each of the physiographic units and soil samples collected from the pedogenetic horizons for the analysis of some heavy metals like Lead (Pb), Copper (Cu), Manganese (Mn), Zinc (Zn), and Iron (Fe). The heavy metals observed in this study were Cu, Mn, Zn and Fe while Pb was not detected in this study. The results of this study showed that the grass land, continuously cropped and forest land had no Pb detected. The heavy metal contents(Cu, Mn, Zn and Fe) detected decreases with depth from 0.15cm depth to 60-90 cm depth in grass land and continuously cropped and forested land respectively. The occurrence of Fe was high in forested land which ranges from 7.8-6.3Mg/Kg with mean value of 7.0Mg/Kg than continuous cropped land and grass land with lower values. The forest land had high sodium content with mean value of 0.74 and high electrical conductivity with a mean 4.91 dsm-1. The results showed low to moderate heavy metal load in forest land and high to moderate load of heavy metals in the grass land and continuously cropped land.

Loading Recommendations for Muscle Strength, Hypertrophy, and Local Endurance: A Re-Examination of the Repetition Continuum

Loading recommendations for resistance training are typically prescribed along what has come to be known as the “repetition continuum”, which proposes that the number of repetitions performed at a given magnitude of load will result in specific adaptations. Specifically, the theory postulates that heavy load training optimizes increases maximal strength, moderate load training optimizes increases muscle hypertrophy, and low-load training optimizes increases local muscular endurance. However, despite the widespread acceptance of this theory, current research fails to support some of its underlying presumptions. Based on the emerging evidence, we propose a new paradigm whereby muscular adaptations can be obtained, and in some cases optimized, across a wide spectrum of loading zones. The nuances and implications of this paradigm are discussed herein.

Leptin and inflammatory factors play a synergistic role in the regulation of reproduction in male mice through hypothalamic kisspeptin-mediated energy balance

Background Energy balance is closely related to reproductive function, wherein hypothalamic kisspeptin mediates regulation of the energy balance. However, the central mechanism of kisspeptin in the regulation of male reproductive function under different energy balance states is unclear. Here, high-fat diet (HFD) and exercise were used to change the energy balance to explore the role of leptin and inflammation in the regulation of kisspeptin and the hypothalamic-pituitary-testis (HPT) axis. Methods Four-week-old male C57BL/6 J mice were randomly assigned to a normal control group (n = 16) or an HFD (n = 49) group. After 10 weeks of HFD feeding, obese mice were randomly divided into obesity control (n = 16), obesity moderate-load exercise (n = 16), or obesity high-load exercise (n = 17) groups. The obesity moderate-load exercise and obesity high-load exercise groups performed exercise (swimming) for 120 min/day and 120 min × 2 times/day (6 h interval), 5 days/week for 8 weeks, respectively. Results Compared to the mice in the normal group, in obese mice, the mRNA and protein expression of the leptin receptor, kiss, interleukin-10 (IL-10), and gonadotropin-releasing hormone (GnRH) decreased in the hypothalamus; serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), and testosterone levels and sperm quality decreased; and serum leptin, estradiol, and tumor necrosis factor-α (TNF-α) levels and sperm apoptosis increased. Moderate- and high-load exercise effectively reduced body fat and serum leptin levels but had the opposite effects on the hypothalamus and serum IL-10 and TNF-α levels. Moderate-load exercise had anti-inflammatory effects accompanied by increased mRNA and protein expression of kiss and GnRH in the hypothalamus and increased serum FSH, LH, and testosterone levels and improved sperm quality. High-load exercise also promoted inflammation, with no significant effect on the mRNA and protein expression of kiss and GnRH in the hypothalamus, serum sex hormone level, or sperm quality. Moderate-load exercise improved leptin resistance and inflammation and reduced the inhibition of kisspeptin and the HPT axis in obese mice. The inflammatory response induced by high-load exercise may counteract the positive effect of improving leptin resistance on kisspeptin and HPT. Conclusion During changes in energy balance, leptin and inflammation jointly regulate kisspeptin expression on the HPT axis.

An Intense, But Ecologically Valid, Resistance Exercise Session Does Not Alter Growth Factors Associated With Cognitive Health

The purpose of this investigation was to assess the acute changes in growth factors associated with cognitive health following two ecologically valid, intense resistance exercise sessions. Twenty-nine late-middle-aged adults performed one session of either (a) moderate-load resistance exercise or (b) high-load resistance exercise. Venous blood was collected prior to warm-up, immediately following exercise and 30 min following exercise. Serum was analyzed for brain-derived neurotrophic factor, insulin-like growth factor 1, and vascular endothelial growth factor. Session intensity was determined by blood lactate concentration and session rating of perceived exertion. Postexercise blood lactate was greater following moderate-load when compared with high-load resistance exercise. Subjective session intensity was rated higher by the session rating of perceived exertion following moderate-load when compared with high-load resistance exercise. No differences were observed in serum growth factor levels between groups. Ecologically valid and intense moderate-load or high-load exercise methods do not alter serum growth factor levels in late-middle-aged adults.