Combined Blood Flow Restriction Training and Betaine Supplementation Impacts on Serum Betaine and Homocysteine Concentrations

Homocysteine (HCY) is a clinically implicated in inflammation and cardiovascular impairments. Although both betaine supplementation and acute resistance (both high-load [HL] and low-load blood flow restriction [LL-BFR]) training notably attenuate HCY concentrations, it is hitherto unknown if these independent modalities synergistically interact. PURPOSE: to determine whether a combination of betaine supplementation, as well as acute HL and/or LL-BFR training can attenuate post-exercise HCY more effectively than either isolated modality. METHODS: Eighteen recreationally trained males (25±5y) were randomized in double-blind fashion to supplement 6g/day of either betaine anhydrous (BET) or identically dosed cellulose placebo for 14-days. Subsequently, all subjects performed four standardized sets of one-leg press and two additional sets to muscular failure on both legs in a counter-balanced and crossover design. Specifically, one leg performed standard high-load (HL; 70%1RM) exercise and contralateral limb underwent BFR (LL-BFR; 20%1RM) training at 80% arterial occlusion pressure. Serum homocysteine (HCY) and betaine (BET) concentrations were analyzed before and 30-minutes post-exercise prior to quantification via ELISA and liquid chromatography-mass spectrometry, respectively. The changes in all aforementioned variables from baseline (∆HCY and ∆BET) were assessed via separate two-way mixed model ANOVA with repeated measures at a significance level of pRESULTS: Analyses failed to reveal any significant main nor interaction effects for serum ∆BET. Although no apparent main supplement nor interaction effects were observed, ∆HCY demonstrated a significant main exercise condition effect (p=.045; ηp2=.228), whereby the LL-BFR group displayed significantly greater concentrations versus HL (p=.045). CONCLUSION: While these findings ultimately do not support a betaine-resistance training synergy-mediated reduction in serum HCY, our data otherwise suggest BFR training may preferentially result in lower post-training concentrations relative to a commonly employed, high-load approach. Future research should elucidate the credence of this interpretation via additional longitudinal investigations amidst hyperhomocysteinemia-predisposed clinical populations

DIFFERENCES IN SEMG BETWEEN NORMAL SQUATS AND ACCENTUATED ECCENTRIC LOADED SQUATS IN COMPETITIVE COLLEGIATE WEIGHTLIFTERS

The purpose of the present work was to compare the effect of accentuated eccentric loaded (AEL) squats to normally loaded (NOR) squats on surface measured muscle activation (sEMG) in competitive weightlifters. Eight experienced, competitive weightlifters (six males, two females) completed both an AEL and NOR squat session (seven days apart), comprised of nine sets of squats, and was identical to their normal scheduled training. sEMG data from the vastus medialis (VM), vastus lateralis (VL), and biceps femoris (BF) was collected (at 1000Hz) during the entirety of the concentric (CON) phases of the AEL and NOR sessions. RMANOVAs (set x session-type) were calculated and no statistical differences were found (p > 0.05) while promising statistical effect sizes (?2 partial 0.073 to 0.273) were observed

Differences in sEMG Between Normal Squats and Accentuated Eccentric Loaded Squats in Competitive Collegiate Weightlifters

The purpose of the present work was to compare the effect of accentuated eccentric loaded (AEL) squats to normally loaded (NOR) squats on surface measured muscle activation (sEMG) in competitive weightlifters. Eight experienced, competitive weightlifters (six males, two females) completed both an AEL and NOR squat session (seven days apart), comprised of nine sets of squats, and was identical to their normal scheduled training. sEMG data from the vastus medialis (VM), vastus lateralis (VL), and biceps femoris (BF) was collected (at 1000Hz) during the entirety of the concentric (CON) phases of the AEL and NOR sessions. RMANOVAs (set x session-type) were calculated and no statistical differences were found (p \u3e 0.05) while promising statistical effect sizes (?2 partial 0.073 to 0.273) were observed

DOES BETA-ALANINE SUPPLEMENTATION POTENTIATE MUSCLE PERFORMANCE FOLLOWING 6 WEEKS OF BLOOD FLOW RESTRICTION OR TRADITIONAL RESISTANCE TRAINING?

International Journal of Exercise Science 16(2): 999-1011, 2023. We aimed to compare the effects of beta-alanine on Traditional Resistance Training (TRAD) or Blood Flow Restriction Training (BFR). Methods: 19 subjects were randomly allocated to a Placebo (n = 10) or beta-alanine (n = 9) group. Subjects from both groups were trained unilaterally (unilateral arm curl) for six weeks, and each arm was trained using a different paradigm (BFR or TRAD). One repetition maximum (1RM) test measurements were performed before and after the strength training program. Work output was accessed as the total weight lifted (repetitions × weight lifted × sets) for the entire strength training program. Results: 1RM or total weight lifted was not increased by beta-alanine supplementation. However, the TRAD-trained arm showed a significantly increased 1RM and total weight lifted compared to the BFR arm (p \u3c 0.05). Conclusion: We conclude that in the short-term (6 weeks) and following the current experimental conditions, beta-alanine does not benefit BFR or TRAD in terms of total weight lifted (volume of training) or maximal strength (1RM)

The acute effects of plyometric and sled towing stimuli with and without caffeine ingestion on vertical jump performance in professional soccer players

Abstract Background Post-activation potentiation (PAP) is the phenomenon by which muscular performance is enhanced in response to a conditioning stimulus. PAP has typically been evidenced via improved counter movement jump (CMJ) performance. This study examined the effects of PAP, with and without prior caffeine ingestion, on CMJ performance. Methods Twelve male professional soccer players (23 ± 5 years) performed two trials of plyometric exercises and sled towing 60 min after placebo or caffeine ingestion (5 mg.kg− 1) in a randomized, counterbalanced and double-blinded design. CMJ performance was assessed at baseline and 1, 3 and 5 min after the conditioning stimulus (T1, T3 and T5, respectively). Results Two way ANOVA main effects indicated a significant difference in jump height after the PAP protocol (F[3, 11] = 14.99, P  0.05) compared to placebo. Conclusions The results of this study suggest that acute plyometric and sled towing stimuli enhances jump performance and that this potentiation is augmented by caffeine ingestion in male soccer players

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo

Meeting Abstracts: Proceedings of the Thirteenth International Society of Sports Nutrition (ISSN) Conference and Expo Clearwater Beach, FL, USA. 9-11 June 201

The Effects of a Sports Nutrition Education Intervention on Nutritional Status, Sport Nutrition Knowledge, Body Composition, and Performance during Off Season Training in NCAA Division I Baseball Players

This study investigated the effects of a sport nutrition education intervention (SNEI) on dietary intake, knowledge, body composition, and performance in NCAA Division I baseball players. Resistance trained NCAA Division I baseball players (82.4 ± 8.2 kg; 1.83 ± 0.06 m; 13.7 ± 5 % body fat) participated in the study during 12 weeks of off-season training. Fifteen players volunteered for SNEI while 15 players matched for position served as controls (C) for body composition and performance. The nutrition intervention group (NI) received a 90 min SNEI encompassing energy intake (Kcal), carbohydrate (CHO), protein (PRO), fat, food sources, and hydration. Sport nutrition knowledge questionnaires were administered to NI pre and post. Nutritional status was determined by three-day dietary logs administered to NI pre and post. Body composition and performance (5-10-5 shuttle test, vertical jump, broad jump, 1 RM squat) were measured pre and post for C and NI. Knowledge increased in NI. Pro and fat, but not CHO intake increased in NI. FM decreased pre to post in NI (11.5 ± 4.8 vs. 10.5 ± 5.4 kg) but not C (11.3 ± 4.7 vs. 11.9 ± 4.5 kg). FFM increased pre to post with no differences between groups. The 5-10-5 shuttle times decreased significantly more in NI (4.58 ± 0.15 vs. 4.43 ± 0.13 sec) compared to C (4.56 ± 0.18 vs. 4.50 ± 0.16 sec). Jump and squat performance increased pre to post with no differences between groups. Our findings indicate that an off season SNEI is effective at improving sport nutrition knowledge and some, but not all, nutrient intakes and performance measures in Division I baseball players

The effects of chronic betaine supplementation on body composition and performance in collegiate females: a double-blind, randomized, placebo controlled trial

Abstract Background Betaine supplementation has been shown to improve body composition and some metrics of muscular performance in young men; but, whether betaine enhances body composition or performance in female subjects is currently unknown. Therefore, the purpose of this study was to investigate the interaction between resistance training adaptation and chronic betaine supplementation in females. Methods Twenty-three young women (21.0 ± 1.4 years, 165.9 ± 6.4 cm, 68.6 ± 11.8 kg) without prior structured resistance training experience volunteered for this study. Body composition (BodPod), rectus femoris muscle thickness (B-mode Ultrasound), vertical jump, back squat 1RM and bench press 1RM were assessed pre- and post-training. Following 1 week of familiarization training, subjects were matched for body composition and squat strength, and randomly assigned to either a betaine (2.5 g/day; n = 11) or placebo (n = 12) group that completed 3 sets of 6–7 exercises per day performed to momentary muscular failure. Training was divided into two lower and one upper body training sessions per week performed on non-consecutive days for 8 weeks, and weekly volume load was used to analyze work capacity. Results Significant main effects of time were found for changes in lean mass (2.4 ± 1.8 kg), muscle thickness (0.13 ± 0.08 cm), vertical jump (1.8 ± 1.6 cm), squat 1RM (39.8 ± 14.0 kg), and bench press 1 RM (9.1 ± 7.3 kg); however, there were no significant interactions. A trend (p = .056) was found for greater weekly training volumes for betaine versus placebo. Significant interactions were found for changes in body fat percentage and fat mass: body fat percentage and fat mass decreased significantly more in betaine (− 3.3 ± 1.7%; − 2.0 ± 1.1 kg) compared to placebo (− 1.7 ± 1.6%; − 0.8 ± 1.3 kg), respectively. Conclusions The results of this study indicated that betaine supplementation may enhance reductions in fat mass, but not absolute strength, that accompany a resistance training program in untrained collegiate females