The meat of the matter: plant-based meat analogue versus traditional meat product nutritional quality

Plant-based meat analogues(PBMA)are formulated to mimic the sensory characteristics of traditional meat products(TMP)using vegetarian ingredients and are increasingly popular with the trend towards plantbased diets,even among meat-eating consumers.This narrative review compared the nutritional quality of PBMA and TMP to broaden the discussion on the suitability of simulated meat products to substitute TMP,while exploring other attributes for their comparison.The complexity of PBMA and TMP means they are not entirely interchangeable.Importantly,PBMA health effects extend beyond their basic nutrient content and quality.Postprandial metabolism and satiety,for example,can be affected by product formulation,ingredient interactions,and thermomechanical processing involved in producing organoleptically acceptable PBMA.There are specific opportunities for low-sodium PBMA products to contribute to a healthy shift toward plantbased diets.In conclusion,PBMA cannot be assumed to be healthier than TMP.They should be designed with comprehensive consideration of composition and processing to ensure they support consumers who are adopting plant-based diets in realizing the theoretical health benefits.

Significance of bilayer-forming phospholipids for skeletal muscle insulin sensitivity and mitochondrial function

Phosphatidylcholine(PC) and phosphatidylethanolamine(PE), which make up the bulk of mammalian cell membrane phospholipids, are recognized for their importance in metabolic health. Perturbations in the ratio of PC:PE can affect membrane integrity and function, which thus have serious health consequences. Imbalance in the hepatic PC and PE membrane content can be linked to metabolic disturbances such as ER stress, fatty liver and insulin resistance. Given that impaired insulin sensitivity underlies the pathology of many metabolic disorders and skeletal muscle is a significant regulator of energy metabolism, it is likely that aberrant phospholipid metabolism in skeletal muscle affects whole-body insulin sensitivity. Sarco/endoplasmic reticulum Ca^(2+) ATPase(SERCA) activity and mitochondrial function respond to alterations in PC:PE ratio and are associated with glucose homeostasis. Moreover, PC and PE content within the mitochondrial membrane influence mitochondrial respiration and biogenesis and thus, metabolic function. As skeletal muscle phospholipids respond to stimuli such as diet and exercise, understanding the implications of imbalances in PC:PE ratio is of great importance in the face of the rising epidemic of obesity related diseases. This review will summarize the current state of knowledge signifying the links between skeletal muscle PC:PE ratio and insulin sensitivity with respects to PC and PE metabolism, SERCA activity, mitochondrial function and exercise.

The relationship of high-intensity cross-training with arterial stiffness

Background'.Central arterial stiffness is a cardiovascular risk factor that can be readily affected through engagement in physical exercise training,with resistance and aerobic exercise having disparate affects.Despite the growing popularity of high-intensity cross-training(HICT),little is currently known about the effects of this mixed modality exercise stimulus on arterial stiffness.Therefore,the purpose of this study was to characterize the arterial stiffness of habitual HICT participants vs.aerobically active and sedentary controls using a cross-sectional design.Methods'.A total of 30 participants were recruited:10 middle-aged long-term participants of HICT(CrossFit)and 20 age,sex,and height matched controls(10 recreationally active,10 sedentary).Central and peripheral pulse wave velocities were measured for the carotid-femoral and femoral-dorsalis pedis arterial segments.Aerobic fitness(maximal oxygen uptake,VChmax)was measured and typical exercise participation rates were self-reported for each group.Results'.HICT participants manifested central pulse wave velocity(PWV)(5.3±1.0 m/s,mean±SD)and VChmax(43±6 mL/kg/min)values nearly identical to active controls.Both active groups had significantly better values than sedentary controls(7.1±1.0 m/s,p≤0.001;and 32±7 mL/kg/min,p=0.01).No differences were observed in peripheral PWV between groups.Conclusion'.Habitual participation in HICT exercise was not associated with increased central nor peripheral arterial stiffness.Long-term HICT participants presented with similar fitness and arterial stiffness as compared with participants who practiced traditional aerobic exercise.Compared to sedentary living,HICT may offer musculoskeletal and cardiovascular health benefits without negatively impacting arterial stiffness.

Effectiveness of royal jelly supplementation in glycemic regulation:A systematic review

BACKGROUND Royal jelly(RJ)has been observed to have therapeutic properties in diabetic individuals,including the reduction of high blood sugar.This systematic review synthesized existing evidence to investigate the effectiveness of RJ supplementation in managing measures of blood glucose.AIM To determine the effectiveness of RJ supplementation on glycemic responses in healthy and non-insulin dependent diabetic adults,as well as animal models of diabetes.METHODS This was a systematic review employing the PRISMA strategy.Peer-reviewed,published articles were extracted from several databases using key words related to target population,intervention and outcome and hand-selected for inclusion.Included articles proceeded to data extraction phase,where information on target parameters and effectiveness of treatment was summarized.Following this,the risk of bias for each included study was evaluated.Then,the long-term and immediate effectiveness of RJ supplementation in glycemic control were assessed using the Grading of Recommendations,Assessment,Development and Evaluations(GRADE)tool,which rates the quality of evidence.RESULTS Of 168 articles extracted from database searching,eighteen were included for analysis in this systematic review.Across the studies,studied populations,intervention styles and outcome measures were largely heterogeneous.Despite this,the results in studies indicate a general trend of positive effect of RJ in glycemic regulation in vitro and in vivo.Additionally,some dose-dependent glycemic effects were observed,along with some large effect sizes.The risk of bias for human and animal studies is generally low-unclear risk,although lack of blinding is a serious concern in both categories.Overall,as per the GRADE tool,the quality of evidence is low,and very low for long-term and immediate effectiveness of RJ,respectively.A major limitation affecting evidence quality is the heterogeneity among included studies.Fasting blood glucose and glucose clearance appear to be most affected by RJ supplementation.CONCLUSION Quality of evidence suggesting that RJ is an effective modulator of glycemic regulation is low for long-term effects of RJ,and very low for immediate effects.

Residual force enhancement due to active muscle lengthening allows similar reductions in neuromuscular activation during position-and force-control tasks

Background:Residual torque enhancement(rTE)is the increase in torque observed during the isometric steady state following active muscle lengthening when compared with a fixed-end isometric contraction at the same muscle length and level of neuromuscular activation.In the rTE state,owing to an elevated contribution of passive force to total force production,less active force is required,and there is a subsequent reduction in activation.In vivo studies of rTE reporting an activation reduction are often performed using a dynamometer,where participants contract against a rigid restraint,resisting a torque motor.rTE has yet to be investigated during a position task,which involves the displacement of an inertial load with positional control.Methods:A total of 12 participants(6 males,6 females;age=22.8±1.1 years,height=174.7±8.6 cm,mass=82.1±37.7 kg;mean±SD)completed torque-and position-matching tasks at 60%maximum voluntary contraction for a fixed-end isometric contraction and an isometric contraction following active lengthening of the ankle dorsiflexors.Results:There were no significant differences in activation between torque-and position-matching tasks(p=0.743),with^27%activation reduction following active lengthening for both task types(p<0.001).Conclusion:These results indicate that rTE is a feature of voluntary,position-controlled contractions.These findings support and extend previous findings of isometric torque-control conditions to position-controlled contractions that represent different tasks of daily living.

Eccentric exercise-induced muscle weakness abolishes sex differences in fatigability during sustained submaximal isometric contractions

Background:Females are typically less fatigable than males during sustained isometric contractions at lower isometric contraction intensities.This sex difference in fatigability becomes more variable during higher intensity isometric and dynamic contractions.While less fatiguing than isometric or concentric contractions,eccentric contractions induce greater and longer lasting impairments in force production.However,it is not clear how muscle weakness influences fatigability in males and females during sustained isometric contractions.Methods:We investigated the effects of eccentric exercise-induced muscle weakness on time to task failure(TTF)during a sustained submaximal isometric contraction in young(18-30 years)healthy males(n=9)and females(n=10).Participants performed a sustained isometric contraction of the dorsiflexors at 35°plantar flexion by matching a 30%maximal voluntary contraction(MVC)torque target until task failure(i.e.,falling below 5%of their target torque for>2 s).The same sustained isometric contraction was repeated 30 min after 150 maximal eccentric contractions.Agonist and antagonist activation were assessed using surface electromyography over the tibialis anterior and soleus muscles,respectively.Results:Males were~41%stronger than females.Following eccentric exercise both males and females experienced an~20%decline in maximal voliuntary contraction torque.TTF was-34%longer in females than males prior to eccentic exercise-induced muscle weakness.However,following eccentric exercise-induced muscle weakness,this sex-related difference was abolished,with both groups having an"45%shorter TTF.Notably,there was~100%greater antagonist activation in the female group during the sustained isometric contraction following exercise-induced weakness as compared to the males.Conclusion:This increase in antagonist activation disadvantaged females by decreasing their TTF,resulting in a blunting of their typical fatigability advantage over males.

Activation reduction following an eccentric contraction impairs torque steadiness in the isometric steady-state

Background:The isometric steady-state following active lengthening is associated with greater torque production and lower activation,as measured by electromyographic activity(EMG),in comparison with a purely isometric contraction(ISO)at the same joint angle.This phenomenon is termed residual force enhancement(RFE).While there has been a great deal of research investigating the basic mechanisms of RFE,little work has been performed to understand the everyday relevance of RFE.The purpose of this study was to investigate whether neuromuscular control strategies differ between ISO and RFE by measuring torque steadiness of the human ankle plantar flexors.Methods:Following ISO maximal voluntary contractions in 12 males(25±4 years),an active lengthening contraction was performed at 15°/s over a 30°ankle excursion,ending at the same joint angle as ISO(5°dorsiflexion;RFE).Surface EMG of the tibialis anterior and soleus muscles was recorded during all tasks.Torque steadiness was determined as the standard deviation(SD)and coefficient of variation(CV)of the torque trace in the ISO and RFE condition during activation-matching(20%and 60%integrated EMG)and torque-matching(20%and 60%maximal voluntary contraction)experiments.Two-tailed,paired t tests were used,within subjects,to determine the presence of RFE/activation reduction(AR)and whether there was a difference in torque steadiness between ISO and RFE conditions.Results:During the maximal and submaximal conditions,there was 5%-9%RFE with a 9%-11%AR(p<0.05),respectively,with no difference in antagonist coactivation between RFE and ISO(p>0.05).There were no differences in SD and CV of the torque trace for the 20%and60%activation-matching or the 60%and maximal torque-matching trials in either the RFE or ISO condition(p>0.05).During the 20%torquematching trial,there were～37%higher values for SD and CV in the RFE as compared with the ISO condition(p<0.05).A significant moderate-to-strong negative relationship was identified between the reduction in torque steadiness following active lengthening and the accompanying AR(p<0.05).Conclusion:It appears that while the RFE-associated AR provides some improved neuromuscular economy,this comes at the cost of increased torque fluctuations in the isometric steady-state following active lengthening during submaximal contractions.

The Spreading Depression Propagation: How Electrochemical Patterns Distort or Create Perception

At the transition from quiescence to propagating waves recorded in isolated retinas, a circular electric current closes in the extracellular matrix;this circular current creates a magnetic torus flow that, when entering quiescent tissue in front of the wave, recruits elements and when leaving behind, helps to build the absolute refractory state. The waving magnetic torus is the consequence of the vortex effect and explains the energy boost that drives propagation. Methods: We interpret experimental results from intrinsic and extrinsic fluorescence dyes, voltage, calcium and pH sensitive, optical signals from isolated retinas, and time series recordings using ion exchange resins: Ca, K, pH, Na, Cl recorded extracellularly at retinas, cerebellums and cortices coupled to spreading depression waves. Finally, we checked the ECoG activity, also a time series, at the transition from after discharges to spreading depression in rat hippocampus. Results: The integrated assessment of the diversified measurements led to the realization that the magnetic flow at the wavefront is a major contributor to the wave propagation mechanisms. This flow couples mass and charge flows as a swirling torus from excited to quiescent tissue. Conclusions: An alternative model of the brain is possible, apart from the classical HH and molecular biology model. Physical chemistry of charged gels and its flows explains the results. The conceptual framework uses far from equilibrium thermodynamics.

Mitochondrial ROS and Aging:Understanding Exercise as a Preventive Tool

Sarcopenia,which is characterized by reduction in muscle mass and strength,contributes to several age-related conditions,including insulin resistance and frailty.Despite the importance of maintaining muscle mass for healthy aging,the mechanisms contributing to sarcopenia are not fully elucidated.Nevertheless,mitochondria appear to play a key role in the underlying condition,and importantly,respond robustly to exercise interventions.Mitochondria are intracellular organelles largely attributed to maintaining ATP concentrations,however,the importance of this organelle in overall cellular homeostasis has been expanded in the last decades to include redox signaling,calcium homeostasis,inflammation,and apoptosis.Several lines of evidence suggest that mitochondrial bioenergetics are altered in aged skeletal muscle,resulting in an increase in reactive oxygen species(ROS)production,while conversely genetic/pharmacological approaches that attenuate mitochondrial ROS promote healthy aging and maintenance of muscle mass.These observations suggest that increased free radicals are one of the bases of the aging process and related sarcopenia.Here,we reviewed the current knowledge regarding mitochondrial function and redox balance in aged human skeletal muscle,highlighting the implications of redox unbalance on skeletal muscle mass maintenance and muscle health.Additionally,we describe the benefits of exercise and nutrition interventions in the context of improving mitochondrial bioenergetics and functional outcomes regarding skeletal muscle mass and function.