The genome and population genomics of allopolyploid Coffea arabica reveal the diversification history of modern coffee cultivars.

Coffea arabica, an allotetraploid hybrid of Coffea eugenioides and Coffea canephora, is the source of approximately 60% of coffee products worldwide, and its cultivated accessions have undergone several population bottlenecks. We present chromosome-level assemblies of a di-haploid C. arabica accession and modern representatives of its diploid progenitors, C. eugenioides and C. canephora. The three species exhibit largely conserved genome structures between diploid parents and descendant subgenomes, with no obvious global subgenome dominance. We find evidence for a founding polyploidy event 350,000-610,000 years ago, followed by several pre-domestication bottlenecks, resulting in narrow genetic variation. A split between wild accessions and cultivar progenitors occurred ~30.5 thousand years ago, followed by a period of migration between the two populations. Analysis of modern varieties, including lines historically introgressed with C. canephora, highlights their breeding histories and loci that may contribute to pathogen resistance, laying the groundwork for future genomics-based breeding of C. arabica.

High quality genomes produced from single MinION flow cells clarify polyploid and demographic histories of critically endangered Fraxinus (ash) species.

With populations of threatened and endangered species declining worldwide, efforts are being made to generate high quality genomic records of these species before they are lost forever. Here, we demonstrate that data from single Oxford Nanopore Technologies (ONT) MinION flow cells can, even in the absence of highly accurate short DNA-read polishing, produce high quality de novo plant genome assemblies adequate for downstream analyses, such as synteny and ploidy evaluations, paleodemographic analyses, and phylogenomics. This study focuses on three North American ash tree species in the genus Fraxinus (Oleaceae) that were recently added to the International Union for Conservation of Nature (IUCN) Red List as critically endangered. Our results support a hexaploidy event at the base of the Oleaceae as well as a subsequent whole genome duplication shared by Syringa, Osmanthus, Olea, and Fraxinus. Finally, we demonstrate the use of ONT long-read sequencing data to reveal patterns in demographic history.

Molecular Phylogenomics Reveals the Deep Evolutionary History of Carnivory across Land Plants.

Plastid molecular phylogenies that broadly sampled angiosperm lineages imply that carnivorous plants evolved at least 11 times independently in 13 families and 6 orders. Within and between these clades, the different prey capture strategies involving flypaper and pitfall structures arose in parallel with the subsequent evolution of snap traps and suction bladders. Attempts to discern the deep ontological history of carnivorous structures using multigene phylogenies have provided a plastid-level picture of sister relationships at the family level. Here, we present a molecular phylogeny of the angiosperms based on nuclear target sequence capture data (Angiosperms-353 probe set), assembled by the Kew Plant Trees of Life initiative, which aims to complete the tree of life for plants. This phylogeny encompasses all carnivorous and protocarnivorous families, although certain genera such as Philcoxia (Plantaginaceae) are excluded. This study offers a novel nuclear gene-based overview of relationships within and between carnivorous families and genera. Consistent with previous broadly sampled studies, we found that most carnivorous families are not affiliated with any single family. Instead, they emerge as sister groups to large clades comprising multiple non-carnivorous families. Additionally, we explore recent genomic studies across various carnivorous clades that examine the evolution of the carnivorous syndrome in relation to whole-genome duplication, subgenome dominance, small-scale gene duplication, and convergent evolution. Furthermore, we discuss insights into genome size evolution through the lens of carnivorous plant genomes.

Combined exercise intervention in a mouse model of high-risk neuroblastoma: effects on physical, immune, tumor and clinical outcomes.

Background: Exercise might exert anti-tumoral effects in adult cancers but this question remains open in pediatric tumors, which frequently show a different biology compared to adult malignancies. We studied the effects of an exercise intervention on physical function, immune variables and tumoral response in a preclinical model of a highly aggressive pediatric cancer, high-risk neuroblastoma (HR-NB). Methods: 6-8-week-old male mice with orthotopically-induced HR-NB were assigned to a control (N = 13) or exercise (5-week combined [aerobic+resistance]) group (N = 17). Outcomes included physical function (cardiorespiratory fitness [CRF] and muscle strength), as well as related muscle molecular indicators, blood and tumor immune cell and molecular variables, tumor progression, clinical severity, and survival. Results: Exercise attenuated CRF decline (p=0.029 for the group-by-time interaction effect), which was accompanied by higher muscle levels of oxidative capacity (citrate synthase and respiratory chain complexes III, IV and V) and an indicator of antioxidant defense (glutathione reductase) in the intervention arm (all p≤0.001), as well as by higher levels of apoptosis (caspase-3, p=0.029) and angiogenesis (vascular endothelial growth factor receptor-2, p=0.012). The proportion of 'hot-like' (i.e., with viable immune infiltrates in flow cytometry analyses) tumors tended to be higher (p=0.0789) in the exercise group (76.9%, vs. 33.3% in control mice). Exercise also promoted greater total immune (p=0.045) and myeloid cell (p=0.049) infiltration within the 'hot' tumors, with a higher proportion of two myeloid cell subsets (CD11C+ [dendritic] cells [p=0.049] and M2-like tumor-associated macrophages [p=0.028]), yet with no significant changes in lymphoid infiltrates or in cirulating immune cells or chemokines/cytokines. No training effect was found either for muscle strength or anabolic status, cancer progression (tumor weight and metastasis, tumor microenvironment), clinical severity, or survival. Conclusions: Combined exercise appears as an effective strategy for attenuating physical function decline in a mouse model of HR-NB, also exerting some potential immune benefits within the tumor, which seem overall different from those previously reported in adult cancers.

Genomic insights into rapid speciation within the world's largest tree genus Syzygium.

Species radiations, despite immense phenotypic variation, can be difficult to resolve phylogenetically when genetic change poorly matches the rapidity of diversification. Genomic potential furnished by palaeopolyploidy, and relative roles for adaptation, random drift and hybridisation in the apportionment of genetic variation, remain poorly understood factors. Here, we study these aspects in a model radiation, Syzygium, the most species-rich tree genus worldwide. Genomes of 182 distinct species and 58 unidentified taxa are compared against a chromosome-level reference genome of the sea apple, Syzygium grande. We show that while Syzygium shares an ancient genome doubling event with other Myrtales, little evidence exists for recent polyploidy events. Phylogenomics confirms that Syzygium originated in Australia-New Guinea and diversified in multiple migrations, eastward to the Pacific and westward to India and Africa, in bursts of speciation visible as poorly resolved branches on phylogenies. Furthermore, some sublineages demonstrate genomic clines that recapitulate cladogenetic events, suggesting that stepwise geographic speciation, a neutral process, has been important in Syzygium diversification.

Urine Specific Gravity Effect on Total and Segmental Body Composition Validity of Multifrequency Bioelectrical Impedance Analysis Compared With Dual Energy X-Ray Absorptiometry.

ABSTRACT: Fleck, SJ, Hayes, A, Stadler, G, Goesch, T, Goldammer, M, and Braun, S. Urine specific gravity effect on total and segmental body composition validity of multifrequency bioelectrical impedance analysis compared with dual energy x-ray absorptiometry. J Strength Cond Res 35(2): 373-384, 2021-The purposes were to compare body composition measures between a specific multifrequency bioelectrical impedance analyzer (InBody770) and dual-energy x-ray absorptiometry (DXA) and determine if hydration status within a specified range affected these measures. Methods included determining urine specific gravity before testing. Urine specific gravity needed to be within typical well-hydrated (n = 37), euhydrated (n = 45), or slightly dehydrated (n = 20) ranges. Segmental and total body composition measures were determined with the InBody770 and by DXA within the same testing session. Paired sample t-tests revealed significant differences (p < 0.005) between InBody770 and DXA for all body composition variables for all 3 hydration statuses, except for trunk fat-free mass (FFM) and trunk fat mass (FM) of the well-hydrated and euhydrated groups and right leg FM and trunk FFM of the slightly dehydrated group. For the total sample (n = 102), InBody770 significantly underestimated total body FM, right arm FFM, left arm FFM, right leg FFM, and left leg FFM with the range of underestimation being between 0.16 and 2.87 kg. The total body FFM by InBody770 was overestimated by 2.33 ± 2.80 kg or 3.6%. Bland-Altman plots supported these results. The major conclusions are that differences between the InBody770 and DXA segmental and total body FFM and FM are not significantly affected by hydration status in the range investigated, and the FM and FFM determined by the 2 devices are generally significantly different.

Tandem gene duplications drive divergent evolution of caffeine and crocin biosynthetic pathways in plants.

BACKGROUND: Plants have evolved a panoply of specialized metabolites that increase their environmental fitness. Two examples are caffeine, a purine psychotropic alkaloid, and crocins, a group of glycosylated apocarotenoid pigments. Both classes of compounds are found in a handful of distantly related plant genera (Coffea, Camellia, Paullinia, and Ilex for caffeine; Crocus, Buddleja, and Gardenia for crocins) wherein they presumably evolved through convergent evolution. The closely related Coffea and Gardenia genera belong to the Rubiaceae family and synthesize, respectively, caffeine and crocins in their fruits. RESULTS: Here, we report a chromosomal-level genome assembly of Gardenia jasminoides, a crocin-producing species, obtained using Oxford Nanopore sequencing and Hi-C technology. Through genomic and functional assays, we completely deciphered for the first time in any plant the dedicated pathway of crocin biosynthesis. Through comparative analyses with Coffea canephora and other eudicot genomes, we show that Coffea caffeine synthases and the first dedicated gene in the Gardenia crocin pathway, GjCCD4a, evolved through recent tandem gene duplications in the two different genera, respectively. In contrast, genes encoding later steps of the Gardenia crocin pathway, ALDH and UGT, evolved through more ancient gene duplications and were presumably recruited into the crocin biosynthetic pathway only after the evolution of the GjCCD4a gene. CONCLUSIONS: This study shows duplication-based divergent evolution within the coffee family (Rubiaceae) of two characteristic secondary metabolic pathways, caffeine and crocin biosynthesis, from a common ancestor that possessed neither complete pathway. These findings provide significant insights on the role of tandem duplications in the evolution of plant specialized metabolism.

Effects of Different Resistance Training Frequencies on Fat in Overweight/Obese Older Women.

AIM: This study compared the effect of different resistance training (RT) frequencies on total, android, gynoid and trunk body fat in overweight/obese older women. METHODS: Fifty-seven overweight/obese older women (66.9±5.3 years and 39.9±4.9% body fat) were randomly assigned to one of three groups: a group performing RT twice a week (G2X), a group performing RT three times a week (G3X), or a non-exercise control group (CG). Both training groups performed the same 12-week RT program consisting of 8 exercises that trained all major muscle groups. Dual-energy X-ray absorptiometry was used to assess body composition. RESULTS: After the intervention period, both G2X and G3X demonstrated significant (P<0.05) reductions in adiposity compared to the CG for total body fat (G2X=-1.7%, G3X=-2.7%, CG=+2.1%), android fat (G2X=-6.2%, G3X=-7.0%, CG=+8.6%), gynoid fat (G2X=-2.5%, G3X=-2.9%, CG=+1.0%), and trunk fat (G2X=-2.5%, G3X=-3.0%, CG=+2.9%), with no significant differences between training groups. CONCLUSION: These results demonstrate that a low-volume 12-week RT program performed two or three times per week causes decreases in total and regional fat deposition with the greatest reductions occurring in the android region.

Effects of Single Set Resistance Training With Different Frequencies on a Cellular Health Indicator in Older Women.

The main purpose of this study was to compare the effects of resistance training (RT) performed two versus three times per week on phase angle (a cellular health indicator) in older women. A total of 39 women (69.1 ± 5.5 years) were randomly assigned to perform a RT program two (G2X) or three (G3X) days per week for 12 weeks. The RT was a whole-body program (eight exercises, one set, 10-15 repetitions). Phase angle, resistance, reactance, and total body water were assessed by bioimpedance spectroscopy. Intracellular water, reactance, and phase angle increased significantly in G2X (2.1%, 3.0%, and 5.6%, respectively) and G3X (5.0%, 6.9%, and 10.3%, respectively) from pretraining to posttraining, with no significant difference between groups. Bioimpedance resistance decreased similarly in both groups (G2X = -1.7% vs. G3X = -3.2%). We conclude that a single set RT program with a frequency of 2 days per week may be sufficient to promote an improvement in cellular health in older women.

Effects of Different Number of Sets of Resistance Training on Flexibility.

The aim of this study was to investigate the effects of six months of training with three different number of sets of resistance training on flexibility in young men. Forty-seven men (mean ± SD age = 24 ± 1yrs; body mass = 79.39 ± 9.12 kg; height = 174.5 ± 5.6 cm) were randomly divided into three training groups performing either one set (G1S), three sets (G3S), or five sets (G5S) of all exercises in a resistance training session or a control group (CG). All groups were assessed pre- and post-training for Sit-and-Reach test and range of motion of 10 joints using goniometry. The training protocol included three weekly sessions and was composed of nine exercises performed at a moderate intensity (eight to 12RM). The results demonstrated significant differences pre- to post-training for the Sit-and-Reach test for all training groups; however, only the G5S showed significant differences when compared to the CG (31.04 ± 5.94cm vs. 23.56 ± 6.76cm, respectively; p < 0.05). Of the ten joint movements measured, there were range of motion increases only to shoulder flexion (G1S), shoulder extension (G3S), elbow flexion (G3S), and knee flexion (G3S) when comparing pre- to post-training (p < 0.05). In conclusion, different resistance training volumes improved flexibility for some joints of young men. These findings indicate that performing only resistance training can result in increases in flexibility.

Effects of Exercise on the Immune Function of Pediatric Patients With Solid Tumors: Insights From the PAPEC Randomized Trial.

The purpose of this study was to assess the effects of an in-hospital exercise intervention during neoadjuvant chemotherapy on the inflammatory profile and immune cell subpopulation in 20 children with solid tumors (control [n = 11] and exercise group [n = 9]). Although no significant interaction (group × time) effect was found with an analysis of variance test, we found a trend toward an interaction effect for natural killer cells expressing the immunoglobulin-like receptor KIR2DS4, with their numbers remaining stable in the exercise group but increasing in controls. Our data support that exercise interventions are safe in pediatric cancer patients with solid tumors during chemotherapy treatment despite its aggressive, immunosuppressive nature.

Effects of Traditional and Pyramidal Resistance Training Systems on Muscular Strength, Muscle Mass, and Hormonal Responses in Older Women: A Randomized Crossover Trial.

Ribeiro, AS, Schoenfeld, BJ, Fleck, SJ, Pina, FLC, Nascimento, MA, and Cyrino, ES. Effects of traditional and pyramidal resistance training systems on muscular strength, muscle mass, and hormonal responses in older women: a randomized crossover trial. J Strength Cond Res 31(7): 1888-1896, 2017-The purpose of this study was to investigate the effect of resistance training (RT) performed in a pyramid (PR) versus a traditional (TD) system on muscular strength, muscle mass, and hormonal responses in older women. Twenty-five older women (67.6 ± 5.1 years, 65.9 ± 11.1 kg, 154.7 ± 5.8 cm, and 27.5 ± 4.5 kg·m) performed both a TD and PR system RT program in a balanced crossover design. The TD program consisted of 3 sets of 8-12 repetition maximum (RM) with a constant load for the 3 sets, whereas the PR system consisted of 3 sets of 12/10/8-RM with incrementally higher loads for each set. Training was performed in 2 phases of 8 weeks each, with a 12-week washout between the 8-week phases. One repetition maximum (1RM) tests were used as measures of muscular strength. Dual X-ray absorptiometry was used to estimate skeletal muscle mass. Testosterone and IGF-1 concentrations were determined preintervention and postintervention after 12 hours fasting. Significant (p ≤ 0.05) increases were observed in both groups for muscular strength in the 1RM chest press (TD = 12.4% and effect size [ES] = 0.86 vs. PR = 11.5% and ES = 0.74), knee extension (TD = 12.5% and ES = 0.61 vs. PR = 11.8% and ES = 0.62), preacher curl (TD = 10.9% and ES = 0.63 vs. PR = 8.6% and ES = 0.54), and for skeletal muscle mass (TD = 3.6% and ES = 0.32 vs. PR = 2.4% and ES = 0.24) with no differences between groups. There were no significant (p > 0.05) main effects for IGF-1 and testosterone. The results suggest that the PR and TD systems performed are similarly effective for promoting positive adaptations in muscular strength and hypertrophy in older women.

Exercise Intervention in Pediatric Patients with Solid Tumors: The Physical Activity in Pediatric Cancer Trial.

INTRODUCTION: The randomized controlled trial "Physical Activity in Pediatric Cancer" determined the effects of an inhospital exercise intervention combining aerobic and muscle strength training on pediatric cancer patients with solid tumors undergoing neoadjuvant chemotherapy. METHODS: Participants were allocated to an exercise (n = 24, 17 boys; mean ± SEM age, 10 ± 1 yr) or control group (n = 25, 18 boys; 11 ± 1 yr). Training included three sessions per week for 19 ± 2 wk. Participants were assessed at treatment initiation, termination, and 2 months after end treatment. The primary endpoint was muscle strength (as assessed by upper and lower-body five-repetition-maximum tests). Secondary endpoints included cardiorespiratory fitness, functional capacity during daily life activities, physical activity, body mass and body mass index, and quality of life. RESULTS: Most sessions were performed in the hospital's gymnasium. Adherence to the program averaged 68% ± 4% and no major adverse events or health issues were noted. A significant interaction (group-time) effect was found for all five-repetition maximum tests (leg/bench press and lateral row; all P < 0.001). Performance significantly increased after training (leg press: 40% [95% confidence interval [CI], 15-41 kg); bench press: 24% [95% CI, 6-14 kg]; lateral row 25% [95% CI, 6-15 kg]), whereas an opposite trend was found in controls. Two-month post values tended to be higher than baseline for leg (P = 0.017) and bench press (P = 0.014). In contrast, no significant interaction effect was found for any of the secondary endpoints. CONCLUSION: An inhospital exercise program for pediatric cancer patients with solid tumors undergoing neoadjuvant treatment increases muscle strength despite the aggressiveness of such therapy.

The effects of a roundtrip trans-American jet travel on physiological stress, neuromuscular performance, and recovery.

The purpose was to examine the effects of a round trip trans-American jet travel on performance, hormonal alterations, and recovery. Ten matched pairs of recreationally trained men were randomized to either a compression group (COMP) (n = 10; age: 23.1 ± 2.4 yr; height: 174.8 ± 5.3 cm; body mass: 84.9 ± 10.16 kg; body fat: 15.3 ± 6.0%) or control group (CONT) (n = 9; age: 23.2 ± 2.3 yr; height: 177.5 ± 6.3 cm; weight: 84.3 ± 8.99 kg; body fat: 15.1 ± 6.4%). Subjects flew directly from Hartford, CT to Los Angeles, CA 1 day before a simulated sport competition (SSC) designed to create muscle damage and returned the next morning on an overnight flight back home. Both groups demonstrated jet lag symptoms and associated decreases in sleep quality at all time points. Melatonin significantly (P < 0.05) increased over the first 2 days and then remained constant until after the SSC. Epinephrine, testosterone, and cortisol values significantly increased above resting values before and after the SSC with norepinephrine increases only after the SSC. Physical performances significantly decreased from control values on each day for the CONT group with COMP group exhibiting no significant declines. Muscle damage markers were significantly elevated following the SSC with the COMP group having significantly lower values while maintaining neuromuscular performance measures that were not different from baseline testing. Trans-American jet travel has a significant impact on parameters related to jet lag, sleep quality, hormonal responses, muscle tissue damage markers, and physical performance with an attenuation observed with extended wear compression garments.

Effect of resistance training with different frequencies and detraining on muscular strength and oxidative stress biomarkers in older women.

The aim of this study was to compare the effect of resistance training (RT) performed with different frequencies followed by a detraining period on muscular strength and oxidative stress (OS) biomarkers in older women. Twenty-seven physically independent women (68.8 ± 4.8 years, 69.1 ± 14.3 kg, 156.0 ± 6.5 cm, and 28.3 ± 4.9 to kg.m(-2)) were randomly assigned to perform a RT program for 2 or 3 days per week (G2X = 13 vs. G3X = 14) for 12 weeks followed by 12 weeks of detraining period. One repetition maximum (1RM) tests were used as measures of muscular strength (three exercises, three attempts for each exercise, 3-5 min of rest between attempts, and 5 min of rest between exercises). Advanced oxidized protein products (AOPP) and total radical-trapping antioxidant parameter (TRAP) were used as oxidative stress indicators. Both groups increased muscular strength after 12 weeks of training (P < 0.05) in chest press (G2X = +11.9 % vs. G3X = +27.5 %, P < 0.05), knee extension (G2X = +18.4 % vs. G3X = +16.7 %, P > 0.05), and preacher curl (G2X = +37.6 % vs. G3X = +36.7 %, P > 0.05). On the other hand, 12 weeks of detraining were not sufficient to eliminate the major effects produced by RT on muscular strength, although a significant decrease (P < 0.05) has been observed for chest press (G3X = -9.1 % vs. G2X = -10.2 %, P > 0.05), knee extension (G2X = -14.9 % vs. G3X = -12.1 %, P > 0.05), and preacher curl (G2X = -20.5 % vs. G3X = -17.4 %, P > 0.05). Pre- to post-training, both groups showed significant (P < 0.05) increases in TRAP (G2X = +6.9 % vs. G3X = +15.1 %) with no statistical significant difference between the groups (P > 0.05), and the scores remained elevated compared to pre-training after 12 weeks of detraining. AOPP was not changed by RT or detraining (P > 0.05). The results suggest that a 12-week RT program with a frequency of 2 days per week may be sufficient to improve muscular strength and OS in older women and detraining for 12 weeks does not completely reverse the changes induced by RT.

Analysis of the training load during a hypertrophy-type resistance training programme in men and women.

The purpose of this study was to analyze the specific training load during a resistance training (RT) programme designed to increase muscular hypertrophy in men and women. Thirty-four women (22.7 ± 4.1 years, 58.8 ± 11.9 kg, 162.6 ± 6.2 cm and 22.1 ± 3.6 kg.m(-2)) and 30 men (22.7 ± 4.4 years, 68.4 ± 9.0 kg, 174.5 ± 6.6 cm and 22.5 ± 2.4 kg.m(-2)) underwent a supervised RT programme that was divided into two phases of 8 weeks each. Training consisted of 10-12 exercises performed with three sets of 8-12 repetitions at repetition maximum resistances performed 3 times per week on nonconsecutive days. There was a significant (P < 0.05) main effect for gender by time interaction for average training load of all the exercises performed in the first 8 weeks of RT with women showing a higher relative increase than men (+43.6% vs. +32.5%, respectively). This result was not observed during the second 8-week phase of the RT programme during which no significant gender by time interaction (P > 0.05) was shown with both genders having a similar relative increase (+28.7% vs. +24.3%, respectively). Women had a higher increase than men in specific average training load of the upper limb exercises during both the first 8 weeks of training (+30.2% vs. +26.6%, respectively) and the second 8 weeks of training (+31.1% vs. +25.3%, respectively). We conclude that the adaptation in specific training load is influenced by gender.

Dose-response of 1, 3, and 5 sets of resistance exercise on strength, local muscular endurance, and hypertrophy.

The study's purpose was to compare the response of performing 1, 3, and 5 sets on measures of performance and muscle hypertrophy. Forty-eight men, with no weight training experience, were randomly assigned to one of the 3 training groups, 1 SET, 3 SETS, 5 SETS, or control group. All training groups performed 3 resistance training sessions per week for 6 months. The 5 repetition maximum (RM) for all training groups increased in the bench press (BP), front lat pull down (LPD), shoulder press (SP), and leg press (LP) (p ≤ 0.05), with the 5 RM increases in the BP and LPD being significantly greater for 5 SETS compared with the other training groups (p ≤ 0.05). Bench press 20 RM in the 3-SET and 5-SET groups significantly increased with the increase being significantly greater than the 1-SET group and the 5-SET group increase being significantly greater than the 3-SET group (p ≤ 0.05). LP 20 RM increased in all training groups (p ≤ 0.05), with the 5-SETS group showing a significantly greater increase than the 1-SET group (p ≤ 0.05). The 3-SET and 5-SET groups significantly increased elbow flexor muscle thickness (MT) with the 5-SET increase being significantly greater than the other 2 training groups (p ≤ 0.05). The 5-SET group significantly increased elbow extensor MT with the increase being significantly greater than the other training groups (p ≤ 0.05). All training groups decreased percent body fat, increased fat-free mass, and vertical jump ability (p ≤ 0.05), with no differences between groups. The results demonstrate a dose-response for the number of sets per exercise and a superiority of multiple sets compared with a single set per exercise for strength gains, muscle endurance, and upper arm muscle hypertrophy.

Influence of strength training variables on strength gains in adults over 55 years-old: a meta-analysis of dose-response relationships.

OBJECTIVES: The importance of strength training to elderly individuals is well established. However, the dose-response relationship of the benefits of strength training in this population is unclear. The purpose of the study was to use meta-analysis to investigate the dose-response of the effects of strength training in elderly individuals. DESIGN: Fifteen studies with a total of 84 effect-sizes were included. The analyses examined the dose-response relationships of the following training variables 'intensity', 'number of sets', 'weekly frequency', and 'training duration' on strength improvement. METHODS: The studies selected met the following inclusion criteria: (a) randomized controlled trials; (b) trained healthy subjects of both genders; (c) trained subjects aged 55 years or older; (d) strength increases were determined pre- and post-training; (e) use of similar strength evaluation techniques (strength determined by a repetition maximum test) and training routine (dynamic concentric-eccentric knee extension exercise to train the quadriceps muscle group). The effect-sizes were calculated using fixed and random effect models with the main effects determined by meta-regression. RESULTS: Many combinations of training variables resulted in strength increases. However meta-regression indicated only "training duration" had a significant dose-response relationship to strength gains (p=0.001). Over durations of 8-52 weeks, longer training durations had a greater effect on strength gains compared to shorter duration protocols. CONCLUSIONS: Resistive training causes strength gains in elderly individuals, provided the training duration is sufficiently long, regardless of the combination of other training variables.

Benefits of combining inspiratory muscle with 'whole muscle' training in children with cystic fibrosis: a randomised controlled trial.

BACKGROUND: The purpose of this study (randomised controlled trial) was to assess the effects of an 8-week combined 'whole muscle' (resistance+aerobic) and inspiratory muscle training (IMT) on lung volume, inspiratory muscle strength (PImax) and cardiorespiratory fitness (VO2 peak) (primary outcomes), and dynamic muscle strength, body composition and quality of life in paediatric outpatients with CF (cystic fibrosis, secondary outcomes). We also determined the effects of a detraining period. METHODS: Participants were randomly allocated with a block on gender to a control (standard therapy) or intervention group (initial n=10 (6 boys) in each group; age 10±1 and 11±1 years). The latter group performed a combined programme (IMT (2 sessions/day) and aerobic+strength exercises (3 days/week, in-hospital)) that was followed by a 4-week detraining period. All participants were evaluated at baseline, post-training and detraining. RESULTS: Adherence to the training programme averaged 97.5%±1.7%. There was a significant interaction (group×time) effect for PImax, VO2peak and five-repetition maximum strength (leg-press, bench-press, seated-row) (all (p<0.001), and also for %fat (p<0.023) and %fat-free mass (p=0.001), with training exerting a significant beneficial effect only in the intervention group, which was maintained after detraining for PImax and leg-press. CONCLUSION: The relatively short-term (8-week) training programme used here induced significant benefits in important health phenotypes of paediatric patients with CF. IMT is an easily applicable intervention that could be included, together with supervised exercise training in the standard care of these patients.