Comparison of Force Measures Between Start Position, Transition Phase, and Midthigh Pull With Weightlifting Performance During Israel National Competition.

ABSTRACT: Ben-Zeev, T, Sadres, E, and Hoffman, JR. Comparison of force measures between start position, transition phase, and midthigh pull with weightlifting performance during Israel National Competition. J Strength Cond Res 37(11): 2200-2205, 2023-This study compared the relationship between peak force (PKF) and rate of force development (RFD) at isometric start position pull (ISPP), isometric transition position pull (ITPP), and isometric midthigh pull (IMTP) with the snatch (SN), clean and jerk (C&J), and total score (TOT) in 30 national and international Israeli weightlifters (18 men and 12 women). All measures were collected either 1 week before or 1 week after the Israel weightlifting championship. A significant correlation was observed between peak force at all pull positions and performance in the SN, C&J, and TOT for men, women, and both sexes combined ( p < 0.001). The correlations were all very strong (e.g., r values all above 0.90) for both ISPP and ITPP, and all weightlifting performance variables, whereas the correlation between IMTP and weightlifting performance ranged from moderate ( r = 0.69) to strong ( r = 0.89). In addition, significant differences were observed between the correlation coefficient value in ISPP and ITPP with the TOT score compared with the correlations observed in IMTP ( z = 0.7, p = 0.046, and z = 1.7, p = 0.049, respectively). Significant differences were also observed in the women group for ISPP for the SN and TOT score compared with the correlation in IMTP ( z = 1.72, p = 0.043, and z = 1.75, p = 0.040, respectively). Rate of force development at 250 milliseconds significantly ( p values <0.05) correlated with the SN, C&J, and TOT in women ( r 's = 0.65, 0.68, and 0.67, respectively), and when both sexes were combined ( r 's = 0.59, 0.61, and 0.60, respectively), but not for the men. Results of this investigation indicated the importance of isometric force capabilities at ISPP and ITPP for weightlifting performance.

The Effect of Exercise on Neurogenesis in the Brain.

BACKGROUND: The connection between physical exercise and the brain has long been studied. The evidence showing that physical exercise plays a significant role on neurogenesis and cognitive function has primarily been based on research examining aerobic exercise. In this review, we described three exercise modalities: aerobic, anaerobic, and resistance exercise and their impact on brain plasticity and cognitive function. While each of these exercise modalities have been demonstrated to positively influence brain plasticity and cognitive function, the specific mechanism that stimulates these changes appear to differ to some degree between these training modalities. The effect of aerobic and anaerobic exercise appears to be primarily mediated by changes in expression of brain-derived neurotrophic factor (BDNF), lactate, vascular endothelial growth factor (VEGF), and several additional proteins within the brain. However, resistance exercise appears to influence brain plasticity by myokines such as irisin, insulin-growth factor-1 (IGF1), and BDNF that are secreted from skeletal tissue and stimulate neurogenesis within the brain. In addition to the various training modes, manipulation of various acute program variables such as intensity, volume, and rest intervals leads to numerous possible training paradigms that can provide a different stimulus for neurogenesis. This review focuses on the three primary training modes and their connection to neurogenesis and cognitive function.

ß-Alanine supplementation improves fractional anisotropy scores in the hippocampus and amygdala in 60-80-year-old men and women.

Recently, ß-alanine (BA) supplementation was shown to improve cognitive function in older adults with decreased cognitive function. Mechanisms supporting these improvements have not been well defined. This study examined the effects of 10-weeks of BA supplementation on changes in circulating brain inflammatory markers, brain derived neurotrophic factor (BDNF), and brain morphology. Twenty participants were initially randomized into BA (2.4 g·d-1) or placebo (PL) groups. At each testing session, participants provided a resting blood sample and completed the Montreal cognitive assessment (MoCA) test and magnetic resonance imaging, which included diffusion tensor imaging to assess brain tissue integrity. Only participants that scored at or below normal for the MoCA assessment were analyzed (6 BA and 4 PL). The Mann-Whitney U test was used to examine Δ (POST-PRE) differences between the groups. No differences in Δ scores were noted in any blood marker (BDNF, CRP, TNF-α and GFAP). Changes in fractional anisotropy scores were significantly greater for BA than PL in the right hippocampus (p = 0.033) and the left amygdala (p = 0.05). No other differences were noted. The results provide a potential mechanism of how BA supplementation may improve cognitive function as reflected by improved tissue integrity within the hippocampus and amygdala.

Early Life Androgen Administration Attenuates Aging Related Declines in Muscle Protein Synthesis.

PURPOSE: This study examined the acute and long-term effects of nandrolone decanoate (ND) on fractional synthetic rates (FSR). METHODS: Male C57BL/6 mice were randomized into ND ( n = 20) or sham ( n = 20) groups. ND injections (10 g·kg -1 ·wk -1 ) started at 7 months of ages and continued for 6 wk. Ten animals from each group were randomly separated and examined 1 wk following drug cessation. The remaining animals were examined at 16 months of age. Animals were injected IP with 1.5 mL of deuterated water 24 h before euthanasia. The kidney, liver, heart, gastrocnemius, and soleus were extracted. Samples were analyzed for deuterated alanine enrichment in the bound protein and intracellular fraction by liquid chromatography tandem mass spectrometry to measure estimated FSR (fraction/day (F/D)) of mixed tissue. RESULTS: One-way ANOVA, with treatment and age as fixed factors, indicated that kidney FSR was greater ( P = 0.027) in ND (0.41 ± 0.02 F/D) than sham (0.36 ± 0.014F/D) and higher ( P = 0.003) in young (0.42 ± 0.2 F/D) than old (0.35 ± 0.01 F/D). Liver and heart FSR values were greater ( P ≤ 0.001) in young (0.79 ± 0.06 F/D and 0.13 ± 0.01 F/D, respectively) compared with old (0.40 ± 0.01 F/D and 0.09 ± 0.01 F/D, respectively), but not between ND and sham. Gastrocnemius FSR was ( P ≤ 0.001) greater in young (0.06 ± 0.01 F/D) compared with old (0.03 ± 0.002 F/D), and greater ( P = 0.006) in ND (0.05 ± 0.01 F/D) compared with sham (0.04 ± 0.003 F/D). Soleus FSR rates were greater ( P = 0.050) in young (0.13 ± 0.01 F/D) compared with old (0.11 ± 0.003 F/D), but not between ND (0.12 ± 0.01 F/D) and sham (0.12 ± 0.01 F/D). Old animals who had received ND displayed elevated FSR in the gastrocnemius ( P = 0.054) and soleus ( P = 0.024). CONCLUSIONS: ND use in young adult animals appeared to maintain long-term elevations in FSR in muscle during aging.

Role of ß-Alanine Supplementation on Cognitive Function, Mood, and Physical Function in Older Adults; Double-Blind Randomized Controlled Study.

This study investigated 10 weeks of ß-alanine (BA) supplementation on changes in cognitive function, mood, and physical performance in 100 older adults (70.6 ± 8.7 y). Participants were randomized into a BA (2.4 g·d-1) or placebo (PL) group. Testing occurred prior to supplementation (PRE), at the midpoint (MID), and at week-10 (POST). Participants completed cognitive function assessments, including the Montreal cognitive assessment (MOCA) and the Stroop pattern recognition test, at each testing session. Behavioral questionnaires [i.e., the profile of mood states, geriatric depression scale (GDS), and geriatric anxiety scale (GAS)] and physical function assessments (grip strength and timed sit-to-stand) were also conducted. No difference between groups was noted in MoCA scores (p = 0.19). However, when examining participants whose MOCA scores at PRE were at or below normal (i.e., ≤26), participants in BA experienced significant improvements in MOCA scores at MID (13.6%, p = 0.009) and POST (11.8%, p = 0.016), compared to PL. No differences were noted in mood scores, GAS, or any of the physical performance measures. A significant decrease was observed in the GDS for participants consuming BA but not in PL. Results suggested that BA supplementation can improve cognitive function in older adults whose cognitive function at baseline was at or below normal and possibly reduce depression scores.

Examination of Amorphous Calcium Carbonate on the Inflammatory and Muscle Damage Response in Experienced Resistance Trained Individuals.

The effect of 3 weeks of amorphous calcium carbonate (ACC) supplementation (2000 mg per day) was examined on the recovery response to resistance exercise. Thirty men were randomized into a supplement (ACC) or placebo (PL) group. Following supplementation, participants performed six sets of 10 repetitions in the bench press (BP) and incline BP exercises, using 80% of maximal strength. Participants returned 24 (T4) and 48 h (T5) later and performed six sets of the BP exercise. Significant decreases in the number of repetitions (p < 0.001), peak power (p < 0.001), and mean power (p = 0.009) were noted over time, but no significant interactions were observed (p > 0.05). Magnitude-based inference analysis (MBI) indicated that the change in repetitions was possibly beneficial for ACC at T4 and likely beneficial at T5. No significant interaction was noted for general soreness (p = 0.452), but a trend toward an interaction was observed in upper body soreness (p = 0.089). Confidence intervals for mean percent change scores indicated significant differences between the groups at T4 and T5, and MBI analysis indicated that ACC was very likely or likely to be beneficial for reducing soreness at those time points. In conclusion, ACC supplementation may have a potential beneficial effect in attenuating the decline in performance, which is possibly due to the carbonate component.

High-Intensity Functional Training: Molecular Mechanisms and Benefits.

High-intensity interval training (HIIT) and strength exercise are known to improve health markers, such as cardiovascular health, metabolic health, and cognitive function, as well as to reduce all-cause mortality. High-Intensity Functional Training (HIFT) is a training paradigm derived from both HIIT and strength exercise to elicit greater muscle recruitment than repetitive aerobic exercises, thereby improving both cardiovascular fitness and strength parameters. Herein, we provide a focused review of the known molecular mechanisms that underlie the beneficial effects of HIFT on cardiovascular, metabolic, and cognitive functions.

Manipulation of Dietary Intake on Changes in Circulating Testosterone Concentrations.

Elevations in the circulating concentration of androgens are thought to have a positive effect on the anabolic processes leading to improved athletic performance. Anabolic-androgenic steroids have often been used by competitive athletes to augment this effect. Although there has been concerted effort on examining how manipulating training variables (e.g., intensity and volume of training) can influence the androgen response to exercise, there has been much less effort directed at understanding how changes in both macronutrient and micronutrient intake can impact the androgen response. Thus, the focus of this review is to examine the effect that manipulating energy and nutrient intake has on circulating concentrations of testosterone and what the potential mechanism is governing these changes.

The Effects of High-intensity Functional Training (HIFT) on Spatial Learning, Visual Pattern Separation and Attention Span in Adolescents.

Aerobic, anaerobic, and strength exercises are known to improve various cognitive functions, such as executive functions, pattern separation, and working memory. High-intensity functional training (HIFT) is a form of physical activity that can be modified to any fitness level and elicits greater muscle recruitment than repetitive aerobic exercises, thereby improving cardiovascular endurance, strength, and flexibility. HIFT emphasizes functional, multi-joint movements via high-intensity interval training (HIIT) and muscle-strengthening exercises. It is yet unknown, however, whether HIFT affects cognitive functions in adolescents. To address this question, we subjected adolescents to 3 × 20 min training sessions/week of HIFT for 3 months. The effects of HIFT were tested on performance in: (1) virtual reality (VR)-based spatial learning task; (2) computerized visual pattern separation; and (3) attention span. The control group performed a typical physical class three times per week. The effects on cognition were tested at baseline and following 3 months of HIFT. Three months into the intervention, the HIFT group achieved higher scores in the spatial learning task, pattern separation task, and in the attention span test, compared with controls. These data suggest that HIFT can potentially translate into improving school performance in adolescents.

Mild Physical Activity Does Not Improve Spatial Learning in a Virtual Environment.

It is well-established that physical exercise in humans improves cognitive functions, such as executive functions, pattern separation, and working memory. It is yet unknown, however, whether spatial learning, long known to be affected by exercise in rodents, is also affected in humans. In order to address this question, we recruited 20 healthy young male adults (18-30 years old) divided into exercise and control groups (n = 10 in each group). The exercise group performed three sessions per week of mild-intensity aerobic exercise for 12 weeks, while the control group was instructed not to engage in any physical activity. Both groups performed maximal oxygen uptake (VO2max) tests to assess their cardiovascular fitness at baseline and every 4 weeks through the 12 weeks of the training program. The effects of mild aerobic exercise were tested on performance in two different virtual reality (VR)-based spatial learning tasks: (1) virtual Morris water maze (VMWM) and (2) virtual Radial arm water maze (VRAWM). Subjects were tested in both tasks at baseline prior to the training program and at the end of 12 weeks training program. While the mild-intensity aerobic exercise did not affect subjects' VO2max parameters, mean time to anaerobic threshold increased for the exercise group compared with control. No effect was observed, however, on performance in the VMWM or VRAWM between the two groups. Based on these results, we suggest that mild-intensity aerobic exercise does not improve spatial learning and memory in young, healthy adults.