The effects of exercise on VO2peak, quality of life and hospitalization in heart failure patients: A systematic review with meta-analyses

Exercise training has become one of the most fundamental components of cardiac rehabilitation. This systematic review with meta-analyses has the objective to determine the effectiveness of exercise on selected cardiac rehabilitation outcomes, i.e. peak oxygen consumption (VO₂peak), hospitalization and quality of life (QOL) of patients with heart failure. PubMed, EMBASE, and Cochrane Library were searched up to May 2019 to identify randomized controlled trials comparing exercise training to usual care. Overall, 131 trials were included with a total of 9,761 patients, the majority of whom were males (74%), predominantly with reduced ejection fraction and NYHA class ranging from II to III. There was a significant improvement in VO₂peak in the exercise group compared to non-exercise control group (mean difference: 2.98 mL/kg/ min, 95% CI: 2.52-3.43, p < 0.001; 84 RCTs, n = 3,690 patients). Exercise training was also beneficial for the patients' QOL. The QOL meta-analysis included 5,786 patients and showed a clinically significant improvement of QOL following exercise (-0.82, 95% CI: -1.02 to -0.62; p = 0.00001; I² = 91%). Hospitalization incidence of heart failure patients was also lower in the exercise compared to control group (fixed-effect Odds Ratio: 0.56, 95% CI: 0.42-0.75, p < 0.0001; 26 trials, 4,664 participants). Exercise-based rehabilitation improves V0₂peak and QOL and reduces the incidence of hospitalization of heart failure patients.

Effect of a Carbohydrate-Electrolyte Solution on Fluid Balance and Performance at a Thermoneutral Environment in International-Level Fencers

Chryssanthopoulos, C, Tsolakis, C, Bottoms, L, Toubekis, A, Zacharogiannis, E, Pafili, Z, and Maridaki, M. Effect of a carbohydrate-electrolyte solution on fluid balance and performance at a thermoneutral environment in international-level fencers. J Strength Cond Res 34(1): 152-161, 2020-The purpose of the study was to examine a possible effect of a carbohydrate-electrolyte (CHO-E) solution on fluid balance and performance in fencing at a thermoneutral environment. Sixteen fencers performed two 120-minute training sessions separated by 7-14 days under similar environmental conditions (temperature: 20.3° C and humidity: 45-47%). Each session consisted of 60-minute conditioning exercises followed by 10 bouts of 3 minutes against the same opponent with 3-minute interval between each bout. Participants ingested at regular intervals either a 6% CHO-E solution or an artificially sweetened water (PL) in a counterbalanced order. No difference was observed between conditions in the heart rate responses, perceived exertion, changes in plasma volume, urine specific gravity, number of bouts won or lost, or points for and against. Considerable variability was observed in body mass changes that revealed significant differences at the time level (i.e., pre- vs. post-exercise) (F1,15 = 9.31, p = 0.008, η = 0.38), whereas no difference was found between conditions (i.e., CHO-E vs. PL) (F1,15 = 0.43, p = 0.52, η = 0.03) and conditions × time interaction (F1,15 = 3.57, p = 0.078, η = 0.19). Fluid loss was not significantly different between conditions (p = 0.08, d = 0.47). The blood glucose level was higher (p < 0.01) after exercise in CHO-E, whereas the blood lactate level was similar between conditions. In conclusion, the CHO-E solution was as effective as the artificially sweetened water in terms of fluid balance and fencing performance at a thermoneutral environment. Because of large individual variability, fencers should monitor their fluid intake and body fluid loss in training and competition.

THE EFFECT OF 6-WEEKS WHOLE BODY VIBRATION ON MUSCULAR PERFORMANCE ON YOUNG NON-COMPETITIVE FEMALE ARTISTIC GYMNASTS

The purpose of this study was to investigate the effects of a 6-week whole body vibration-intervention on muscle performance and flexibility on gymnasts. Twenty-two young non-competitive-moderate trained gymnasts that volunteered to participate in the study separated into either the vibration group or the no vibration group according to their training regime. The vibration intervention consisted of a 6-week whole-body vibration, 3 times per week and involved eccentric and concentric squatting movements on a vibration platform with the participants performing three exercises on the vibration device whereas for the no vibration group vibration platform was turned off. Five performance tests (20m running speed, sit & reach test, squat jump, counter movement jump and single leg squat (right leg and left leg) were performed at the beginning of the intervention, and after the end of 6-week intervention program. According to the results significant interaction effect between group and time was found for the running speed and Squat Jump test. On the contrary, significant main effect were found were found for time on the running speed, Squat Jump, Counter movement jump and single leg squat. Conclusively, it has been reported that Whole body vibration is an effective method to improve Squat Jump performance in young non-competitive female artistic gymnasts.

Phosphorus nutritional knowledge among dialysis health care providers and patients: A multicenter observational study

BACKGROUND-AIMS

Phosphorus nutritional knowledge level of hemodialysis patients and renal nurses has been found to be low, while respective knowledge of nephrologists has not been studied yet. There are equivocal results regarding the association of phosphorus nutritional knowledge level and serum phosphorus values. The aim of this study was to assess phosphorus nutritional knowledge of hemodialysis patients, nephrologists and renal nurses and seek potential interventions to improve patients' adherence to phosphorus and overall nutritional guidelines.

METHODS

This cross-sectional observational study was conducted on sixty eight hemodialysis patients, 19 renal nurses and 11 nephrologists who were recruited from 3 hemodialysis units in Greece. Phosphorus nutritional knowledge of the participants was assessed by a 25-item item questionnaire (CKDKAT-N) which included 15 questions on phosphorus and 10 questions on protein, sodium, and potassium knowledge.

RESULTS

Nephrologists had higher CKDKAT-N total (19.1 ± 3.6 vs 14.1 ± 2.8 and 13.2 ± 2.8, P < 0.01) and phosphorus knowledge scores (10.6 ± 2.7 vs 7.6 ± 2.2 and 7.3 ± 2.0, P < 0.01) compared to renal nurses and patients respectively. There were no differences in total and phosphorus knowledge scores between nurses and patients. Patients and nurses answered correctly significantly less questions regarding phosphorus compared with the rest of the questions (P < 0.01) while no such difference was found in nephrologists. Serum phosphorus was positively correlated with phosphorus knowledge score (r = 0.31, P = 0.02), and negatively correlated with patient age (r = -0.34, P < 0.05). None of the patients, 11% of the nurses and 27% of the nephrologists answered correctly all three questions regarding P, K and Na dietary recommendations (P < 0.01).

CONCLUSIONS

The study confirms that hemodialysis patients have low renal nutrition knowledge while higher nutritional phosphorus knowledge does not lead to lower serum phosphorus values. Alarmingly, renal nurses have been found to have a similar level of knowledge with hemodialysis patients, something that needs to be taken into account when training the new dialysis staff. Nephrologists have superior knowledge; however they are still lacking essential nutritional knowledge that could affect patients' and nurses' overall understanding. Continuing education on nutrition of nephrologists and renal nurses could improve nutrition care of hemodialysis patients.

Hormonal responses following eccentric exercise in humans

OBJECTIVE

Mechanically overloaded muscle and its subsequent damage are strong stimuli for eliciting acute hormonal changes, while the muscle adaptation which occurs following exercise-induced muscle damage may involve complex hormonal responses before the completion of muscle regeneration. The purpose of this study was to investigate systemic responses of various hormones, as well as secreted proteins that are exercise-regulated and associated with muscle adaptation, for several days after eccentric exercise-induced muscle damage in humans.

DESIGN

Nine young male volunteers performed 50 maximal eccentric muscle actions using the knee extensor muscles of both legs. Blood samples were drawn before and at 6, 48 and 120 hours post exercise and serum levels of growth hormone (GH), insulin-like growth factor binding protein-3 (IGFBP-3), cortisol, prolactin, thyroid-stimulating hormone (TSH), free thyroxine (fT4), irisin, follistatin and sclerostin were measured. Myoglobin (Mb) concentration and lactate dehydrogenase (LDH) activity were also evaluated as indirect markers of muscle damage.

RESULTS

Significant alterations in Mb and LDH were observed over time after eccentric exercise (p=0.039-0.001). A late serum increase in fT4 and decrease in irisin levels, along with an early and persistent decrease in IGFBP-3 levels, were observed following the muscle-damaging exercise (p=0.049-0.016). GH, cortisol, prolactin, TSH, follistatin and sclerostin exhibited moderate changes during the recovery period after exercise, though without reaching statistical significance (p>0.05), while correlational analyses revealed significant associationsbetween GH and IGFBP-3, prolactin and sclerostin over time (p=0.049-0.001).

CONCLUSIONS

The significant hormonal responses observed in this study may indicate their involvement in the regenerative mechanisms following muscle damage, potentially as part of a regulatory network to support a normal adaptation process after muscle-damaging exercise.

Carbohydrate mouth rinse does not affect performance during a 60-min running race in women

This study examined the effect of carbohydrate mouth rinsing on endurance running performance in women. Fifteen female recreational endurance runners, who used no oral contraceptives, ran two races of 1-h duration on an indoor track (216-m length) at 18:00 h after an 8-h fast with a 7-days interval between races, corresponding to the 3^rd-10th day of each premenopausal runner's menstrual cycle, or any day for the postmenopausal runners. In a double-blind random order, participants rinsed their mouth with 25 ml of either a 6.4% carbohydrate (RCHO) or a placebo solution (RP). No fluid was ingested during exercise. Serum 17β-Εstradiol (P = 0.59) and Progesterone (P = 0.35) did not differ between treatments. There was no difference in 1-hour running performance (RCHO: 10,621.88 ± 205.98 m vs. RP: 10,454.00 ± 206.64 m; t = 1.784, P = 0.096). Furthermore, the mean percentage effect (±99%CI) of RCHO relative to RP, 1.67% (-1.1% to 4.4%), and Cohen's effect size (d = 0.21) support a trivial outcome of RCHO for total distance covered. In conclusion, carbohydrate mouth rinsing did not improve 60-min track running performance in female recreational runners competing in a low ovarian hormone condition, after an 8-h fast and when no fluid was ingested during exercise.