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1.
Article in English | MEDLINE | ID: mdl-33946754

ABSTRACT

The block periodization training paradigm has been shown to produce enhanced gains in strength and power. The purpose of this study is to assess resistance training induced alterations in lean body mass and cross-sectional area using a block periodization training model among individuals (n = 15) of three differing strength levels (high, moderate and low) based on one repetition maximum back squat relative to body weight. A 3 × 5 mixed-design ANOVA was used to examine within-and between-subject changes in cross-sectional area (CSA), lean body mass (LBM), lean body mass adjusted (LBMadjusted) and total body water (TBW) over an 11-week resistance training program. LBMadjusted is total body water subtracted from lean body mass. The ANOVA revealed no statistically significant between-group differences in any independent variable (p > 0.05). Within-group effects showed statistically significant increases in cross-sectional area (p < 0.001), lean body mass (p < 0.001), lean body mass adjusted (p ˂ 0.001) and total body water (p < 0.001) from baseline to post intervention: CSA: 32.7 cm2 ± 8.6; 36.3 cm2 ± 7.2, LBM: 68.0 kg ± 9.5; 70.6 kg ± 9.4, LBMadjusted: 20.4 kg ± 3.1; 21.0 kg ± 3.3 and TBW: 49.8 kg ± 6.9; 51.7 kg ± 6.9. In conclusion, the results of this study suggest subjects experienced an increase in both lean body mass and total body water, regardless of strength level, over the course of the 11-week block periodized program. Gains in lean body mass and cross-sectional area may be due to edema at the early onset of training.


Subject(s)
Resistance Training , Body Composition , Humans , Infant , Male , Muscle Strength , Muscle, Skeletal , Muscles , Posture
2.
Sports (Basel) ; 8(11)2020 Oct 31.
Article in English | MEDLINE | ID: mdl-33142849

ABSTRACT

Some controversy exists as to the most efficacious method of training to achieve enhanced levels of sport performance. Controversy concerning the efficacy of periodization and especially block periodization (BP) likely stems from the use of poorly or untrained subjects versus trained who may differ in their responses to a stimulus. The purpose of this study was to investigate the effect of training status on performance outcomes resulting from 11 weeks of BP training. Fifteen males were recruited for this study and placed into strong (age = 24.3 ± 1.9 years., body mass (BM) = 87.7 ± 8.7 kg, squat: body mass = 1.96 ± 0.16), moderate (age = 25.3 ± 2.7 years., body mass = 100.2 ± 15.5 kg, squat: body mass = 1.46 ± 0.14), or weak (age = 23.2 ± 3.9 yrs., body mass = 83.5 ± 17.1 kg, squat: body mass = 1.17 ± 0.07) groups based on relative strength. Testing was completed at baseline, and after each block which consisted of 1 repetition maximum (1RM) squat, 0 kg static jump (SJ), 0 kg countermovement jump (CMJ), 20 kg SJ, and 20 kg CMJ. Absolute and relative strength were strongly correlated with rates of improvement for absolute strength, relative strength, 0 kg, and 20 kg vertical jumps. All subjects substantially improved back squat (p < 0.001), relative back squat (p < 0.001) with large-very large effect sizes between groups for percent change favoring the weak group over the moderate and strong group for all performance variables. All subjects showed statistically significant improvements in 0 kg SJ (p < 0.001), 0 kg CMJ (p < 0.001), 20 kg SJ (p = 0.002), and 20 kg CMJ (p < 0.001). Statistically significant between group differences were noted for both 20 kg SJ (p = 0.01) and 20 kg CMJ (p = 0.043) with the strong group statistically greater jump heights than the weak group. The results of this study indicate BP training is effective in improving strength and explosive ability. Additionally, training status may substantially alter the response to a resistance training program.

3.
Acta Biomater ; 112: 101-111, 2020 08.
Article in English | MEDLINE | ID: mdl-32522716

ABSTRACT

While the benefits of both hydrogels and drug delivery to enhance wound healing have been demonstrated, the highly hydrophilic nature of hydrogels creates challenges with respect to the effective loading and delivery of hydrophobic drugs beneficial to wound healing. Herein, we utilize pressurized gas expanded liquid (PGX) technology to produce very high surface area (~200 m2/g) alginate scaffolds and describe a method for loading the scaffolds with ibuprofen (via adsorptive precipitation) and crosslinking them (via calcium chelation) to create a hydrogel suitable for wound treatment and hydrophobic drug delivery. The high surface area of the PGX-processed alginate scaffold facilitates >8 wt% loading of ibuprofen into the scaffold and controlled in vitro ibuprofen release over 12-24 h. In vivo burn wound healing assays demonstrate significantly accelerated healing with ibuprofen-loaded PGX-alginate/calcium scaffolds relative to both hydrogel-only and untreated controls, demonstrating the combined benefits of ibuprofen delivery to suppress inflammation as well as the capacity of the PGX-alginate/calcium hydrogel to maintain wound hydration and facilitate continuous calcium release to the wound. The use of PGX technology to produce highly porous scaffolds with increased surface areas, followed by adsorptive precipitation of a hydrophobic drug onto the scaffolds, offers a highly scalable method of creating medicated wound dressings with high drug loadings. STATEMENT OF SIGNIFICANCE: While medicated hydrogel-based wound dressings offer clear advantages in accelerating wound healing, the inherent incompatibility between conventional hydrogels and many poorly water-soluble drugs of relevance in wound healing remains a challenge. Herein, we leveraged supercritical fluids-based strategies to both process and subsequently impregnate alginate, followed by post-crosslinking to form a hydrogel, to create a very high surface area alginate hydrogel scaffold loaded with high hydrophobic drug contents (here, >8 wt% ibuprofen) without the need for any pore-forming additives. The impregnated scaffolds significantly accelerated burn wound healing while also promoting regeneration of the native skin morphology. We anticipate this approach can be leveraged to load clinically-relevant and highly bioavailable dosages of hydrophobic drugs in hydrogels for a broad range of potential applications.


Subject(s)
Burns , Hydrogels , Alginates , Bandages , Burns/drug therapy , Humans , Wound Healing
4.
Food Res Int ; 106: 354-362, 2018 04.
Article in English | MEDLINE | ID: mdl-29579935

ABSTRACT

The physicochemical properties of the oat beta-glucan powder (BG) and coenzyme Q10 (CoQ10)-loaded BG powder (L-BG) produced by the pressurized gas-expanded liquid (PGX) technology were studied. Helium ion microscope, differential scanning calorimeter, X-ray diffractometer, AutoSorb iQ and rheometer were used to determine the particle morphology, thermal properties, crystallinity, surface area and viscosity, respectively. Both BG (7.7µm) and L-BG (6.1µm) were produced as micrometer-scale particles, while CoQ10 nanoparticles (92nm) were adsorbed on the porous structure of L-BG. CoQ10 was successfully loaded onto BG using the PGX process via adsorptive precipitation mainly in its amorphous form. Viscosity of BG and L-BG solutions (0.15%, 0.2%, 0.3% w/v) displayed Newtonian behavior with increasing shear rate but decreased with temperature. Detailed characterization of the physicochemical properties of combination ingredients like L-BG will lead to the development of novel functional food and natural health product applications.


Subject(s)
Technology, Pharmaceutical/methods , Ubiquinone/analogs & derivatives , beta-Glucans/chemistry , Adsorption , Calorimetry, Differential Scanning , Chemical Phenomena , Chemical Precipitation , Crystallization , Dietary Supplements , Drug Carriers/chemistry , Hot Temperature , Nanoparticles , Powders , Pressure , Rheology , Surface Properties , Ubiquinone/administration & dosage , Ubiquinone/chemistry , Viscosity , X-Ray Diffraction , beta-Glucans/administration & dosage
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