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Background: Vitamin E (α-tocopherol) is an essential micronutrient for human health and optimal physiological function. Inadequacy may be common due to a lack of bioavailability. The use of dietary lipids alongside other emulsification agents may elicit more robust serum concentrations of α-tocopherol via improved bioavailability. Therefore, the aim of the study was to examine oral bioavailability of two delivery methods of α-tocopherol, (1) a microemulsion gel formula composed of dietary lipids and other emulsification agents and (2) a dry solid tablet over 12 hours. Methods: Twelve participants (age = 37.3 ± 9.6 years; height = 173.4 ± 11.8 cm; body mass = 71.2 ± 10.0 kg) participated in a double-blind, randomized, crossover trial comparing two delivery methods both dosed at 288 mg of α-tocopherol. Serum α-tocopherol concentrations were assessed from blood donated by participants at pre-consumption, 2-, 4-, 8-, and 12-hour post-consumption. Study conditions were separated by a 7-day washout. Results: The microemulsion gel formula delivery demonstrated significantly greater area under the curve (p < 0.001) and serum concentration maximums (p = 0.003) for serum α-tocopherol compared to the tablet delivery. No significant differences were detected between conditions for the time to reach concentration maximums (p = 0.375). Conclusion: We conclude that a mixture of dietary lipids and emulsification agents in the form of a microemulsion gel formula was able to significantly improve bioavailability of serum α-tocopherol compared to a tablet by yielding higher serum α-tocopherol maximum concentrations and area under the curve over a 12-hour study period despite dosage being matched. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to explore whether offset loading in the barbell squat altered ground-reaction force (GRF) and muscle activation in the dominant (D) and nondominant (ND) lower limb compared to traditional squats. Methods: Twelve well-trained men (age 26.4 [3.2] y; 10.3 [1.9] y experience) performed 3 sets of 10 repetitions at 60% of their previously measured 1-repetition maximum. Sets were quasi-randomized between traditional loading (TDL), dominant-side offset loading (OS-D), and nondominant-side offset loading (OS-ND). All repetitions were performed on a dual force plate with electromyography sensors on the prime mover muscles of the squat. GRF symmetry was assessed using the symmetry index (SI) to determine the direction (D [+] or ND [−]) and magnitude (%) of the asymmetry. Finally, the first 3 and final 3 repetitions of each set were compared for compensatory changes in symmetry. Results: OS-D induced a significant change in limb SI relative to TDL (5.21% vs 1.44%; P =.011); however, no significant difference in limb SI was seen between TDL and OS-ND (−0.66% vs 1.44%; P =.278). No asymmetries between D and ND muscle activation were present in any condition. TDL and OS-D squats exhibited significant improvements in limb SI between the first 3 and final 3 repetitions (P =.035 and.011, respectively); however, no such improvement was seen in OS-ND. Conclusions: OS-D is capable of significantly altering GRF limb SI in a bilateral squat; however, OS-ND appears to exhibit no GRF or electromyography effects relative to TDL. Thus, the results of this study do not support the use of OS-ND in the pursuit of strengthening a weaker limb, suggesting that unilateral training may be a preferred mode of exercise for this desired outcome. [ABSTRACT FROM AUTHOR]

(1) Background: Iron deficiency without anemia (IDWA) is a prevalent health concern in premenopausal women. Oral supplementation of iron may be a viable solution to improve blood-iron status in women; however, the effects of a high-dose iron-supplement regimen have been associated with gastrointestinal side effects. Therefore, the purpose of the present study was to evaluate the effectiveness of a low-dose liquid fermented iron-bisglycinate supplement (LIS) on improving blood-iron status in premenopausal women with IDWA without increasing constipation or gastrointestinal distress. (2) Methods: 85 premenopausal women with IDWA (ferritin < 70 ng/dL and hemoglobin > 11.0 g/dL) took a LIS (27 mg) or a placebo (PLA) for 8 weeks. Blood draws were taken at Wk0 and Wk8 of the study to measure serum-iron markers. In addition, surveys of gastrointestinal distress were administered at Wk0, Wk4, and Wk8 while the profile of mood states (POMS) was surveyed at Wk0 and Wk8. (3) Results: Compared to the placebo, the LIS was able to increase serum ferritin (p = 0.03), total serum iron (p = 0.03), and mean corpuscular volume (p = 0.02), while exhibiting no significant interaction in subjective gastrointestinal distress (p > 0.05). No significant effects were detected for POMS (p > 0.05). (4) Conclusions: Supplementing with LIS appears to improve blood-iron status without causing significant gastrointestinal distress in premenopausal women with IDWA. [ABSTRACT FROM AUTHOR]

One resistance training variable that may be altered to achieve desired outcomes is the range of motion used in training. Generally, the strength and conditioning field has accepted that using a greater range of motion in strength training exercises results in more substantial muscle hypertrophy outcomes. However, this theory has proved to be inconsistently supported in the literature, and to date, no sufficient explanation exists to explain this phenomenon. This review article seeks to outline a novel approach for potentially describing the disparities seen in range of motion research with respect to hypertrophy outcomes by applying the unique length-tension curve of each muscle being examined. As will be discussed in the review, virtually all the results from range of motion studies in various muscles have corresponded to each muscle's length-tension curve; muscles that are active on the descending limb of the curve appear to garner greater hypertrophy from using larger ranges of motion. Conversely, muscles that are not active on the descending limb exhibit similar adaptations despite alterations in range of motion. A novel hypothesis for applying this information to resistance training programs will be presented and discussed. [ABSTRACT FROM AUTHOR]

This study investigated the effects of marine phytoplankton supplementation on 1) perceived recovery and ground reaction forces in humans following a non-functional overreaching resistance-training program and 2) myogenic molecular markers associated with muscle cell recovery in a rat model. In the human trial, a 5-week resistance-training program with intentional overreaching on weeks 2 and 5 was implemented. Results indicate that marine phytoplankton prompted positive changes in perceived recovery at post-testing and, while both marine phytoplankton and placebo conditions demonstrated decreased peak and mean rate of force development following the overreaching weeks, placebo remained decreased at post-testing while marine phytoplankton returned to baseline levels. In the rat model, rats were divided into four conditions: (i) control, (ii) exercise, (iii) exercise + marine phytoplankton 2.55 mg·d-1 , or (iv) exercise+marine phytoplankton 5.1 mg·d-1. Rats in exercising conditions performed treadmill exercise 5 d·wk-1 for 6 weeks. Marine phytoplankton in exercising rats increased positive and decrease negative myogenic factors regulating satellite cell proliferation. Taken together, marine phytoplankton improved perceptual and functional indices of exercise recovery in an overreaching human model and, mechanistically, this could be driven through cell cycle regulation and a potential to improve protein turnover. [ABSTRACT FROM AUTHOR]