Changes in red blood cell parameters during incremental exercise in highly trained athletes of different sport specializations

Background

During physical exercise, the level of hematological parameters change depending on the intensity and duration of exercise and the individual's physical fitness. Research results, based on samples taken before and after exercise, suggest that hematological parameters increase during incremental exercise. However, there is no data confirming this beyond any doubt. This study examined how red blood cell (RBC) parameters change during the same standard physical exertion in athletes representing different physiological training profiles determined by sport discipline.

Methods

The study included 39 highly trained male members of national teams: 13 futsal players, 12 sprinters, and 14 triathletes. We used multiple blood sampling to determine RBC, hemoglobin (Hb), hematocrit value (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), and red blood cell distribution width (RDW) before, during (every 3 min), and after (5, 10, 15, 20, and 30 min) an incremental treadmill exercise test until exhaustion.

Results

There were no significant exercise-induced differences in RBC parameters between athletic groups. No significant changes were recorded in RBC parameters during the low-intensity phase of exercise. RBC, Hb, and Hct increased significantly during incremental physical exercise, and rapidly returned to resting values upon test termination.

Conclusions

The general pattern of exercise-induced changes in RBC parameters is universal regardless of the athlete's physiological profile. The changes in RBC parameters are proportional to the intensity of exercise during the progressive test. The increase in hemoglobin concentration associated with the intensity of exercise is most likely an adaptation to the greater demand of tissues, mainly skeletal muscles, for oxygen.

Sports Participation Promotes Beneficial Adaptations in the Erythrocyte Guanylate Nucleotide Pool in Male Athletes Aged 20-90 Years

Introduction

The guanine nucleotide pool (GTP, guanosine-5'-triphosphate; GDP, guanosine-5'-diphosphate, and GMP, guanosine-5'-monophosphate) is an essential energy donor in various biological processes (eg protein synthesis and gluconeogenesis) and secures several vital regulatory functions in the human body. The study aimed to predict the trends of age-related changes in erythrocyte guanine nucleotides and examine whether competitive sport and related physical training promote beneficial adaptations in erythrocyte guanylate concentrations.

Methods

The study included 86 elite endurance runners (EN) aged 20-81 years, 58 sprint-trained athletes (SP) aged 21-90 years, and 62 untrained individuals (CO) aged 20-68 years.

Results

The concentration of erythrocyte GTP and total guanine nucleotides (TGN) were highest in the SP group, lower in the EN group, and lowest in the CO group. Both athletic groups had higher guanylate energy charge (GEC) values than the CO group (p = 0.012). Concentrations of GTP, TGN, and GEC value significantly decreased, while GDP and GMP concentrations progressively increased with age.

Conclusion

Such a profile of change suggests a deterioration of the GTP-related regulatory function in older individuals. Our study explicitly shows that lifelong sports participation, especially of sprint-oriented nature, allows for maintaining a higher erythrocyte guanylate pool concentration, supporting cells' energy metabolism, regulatory and transcription properties, and thus more efficient overall body functioning.

Combined Analysis of Blood Ammonia and Lactate Levels as a Practical Tool to Assess the Metabolic Response to Training Sessions in Male and Female Sprinters

ABSTRACT

Kantanista, A, Kusy, K, Pospieszna, B, Korman, P, Wieliński, D, and Zieliński, J. Combined analysis of blood ammonia and lactate levels as a practical tool to assess the metabolic response to training sessions in male and female sprinters. J Strength Cond Res 35(9): 2591-2598, 2021-Previous research has mainly focused on blood ammonia and lactate concentration changes in response to exercise in laboratory settings. The aim of this study was to present a combined analysis of blood ammonia and lactate levels obtained during various training sessions performed under real training conditions. Differences between the sexes were also analyzed. The study subjects included 9 male and 8 female sprinters competing at the international level. The two-way analyses of variance, with repeated measures (time × sex), for lactate and blood ammonia concentrations during strength, speed (only lactate), speed with baton exchange, and speed endurance training sessions were significant. Blood ammonia and lactate levels obtained during repeated sprints were higher in male than female athletes. Peak lactate concentrations obtained from different training sessions were different in the female (F(3, 18) = 49.82, p ≤ 0.001, η2 = 0.893) and male (F(3, 21) = 312.26, p ≤ 0.001, η2 = 0.978) athletes; post hoc analyses of the men and women showed differences in maximum lactate concentration between training sessions, except in the speed and strength sessions. Peak ammonia concentrations obtained in the different training sessions were also different in the female (F(3, 18) = 121.06, p ≤ 0.001, η2 = 0.953) and male (F(3, 21) = 196.04, p ≤ 0.001, η2 = 0.965) athletes; in both the men and women, significant differences in maximum blood ammonia concentrations were found between the training sessions, except for the speed and speed with baton exchange training sessions. The results of this study indicate that the combined analysis of lactate and blood ammonia concentration provides the coach with valuable additional information about the level of adenosine triphosphate breakdown, the energy system contribution involved in muscle energy coverage during very short, repeated maximal sprints, and, most importantly, allows the coach to check whether preworkout goals were actually met.

Skeletal Muscle Cell Damage Indicators in Volleyball Players after the Competitive Phase of the Annual Training Cycle

The aim of the study was to evaluate the impact of the competitive phase on physiological and metabolic indices and selected markers of skeletal muscle damage in male volleyball players. The study group consisted of 24 young male volleyball players. During the study, participants underwent two series of measurements, before and after the competitive phase of the annual training cycle. In both study terms, players performed an incremental treadmill running test to determine their ventilatory threshold and maximal oxygen uptake. Venous and capillary blood samples were taken for biochemical analysis. There was no significant difference in the physical fitness level, values of biochemical variables and the level of antioxidant status in the surveyed athletes between the two study terms. Significant changes within skeletal muscle damage markers were observed between the beginning and the end of the competitive period: an increase in the concentration of cellular DNA damage products (8-hydroxy-2'-deoxyguanosine; p < 0.0001) and a decrease in muscle activity of creatine kinase (p<0.05). In spite of the increment in cell damage markers, the unaffected level of physiological and biochemical markers may indicate that the experienced cell destruction did not negatively affect the level of physical fitness. When designing the annual training plan, coaches and athletes need to take into consideration that temporary physiological states - oxidative stress and inflammation - may be required to attain training adaptation.

Chemical and nutritional characteristics of high-fibre rye milling fractions

BACKGROUND

Many studies have demonstrated the potential health benefits of consuming more high-fibre cereal-based food products. Therefore, there is a need to discover new ways to improve the overall nutritional balance of refined cereal products and focus on increasing their dietary fibre content, at the expense of readily digestible carbohydrates.

METHODS

Lab-scale milling and sieving of whole rye grain was used to obtain two fractions rich in dietary fibre. The fractions were analysed and compared, in terms of microstructure, chemical com- position and nutritional quality.

RESULTS

The two fractions significantly obtained differed in their particle size and contents of minerals, available saccharides, and nutritional fractions of starch and dietary fibre and its major components. The total dietary fibre concentrations in the coarse and fine fractions were 50.0 and 36.0 g/100 g, respectively, i.e. three and 2.2 times higher than that of wholegrain rye flour. Both fractions also differed in their relative proportions of major fibre components. In the fine fraction, the levels of soluble fibre, as well as soluble arabinoxylans and fructans, were significantly higher than those in the coarse fraction.

CONCLUSIONS

It was shown that the application of a simple dry-fractionation method to wholemeal rye flour allows the preparation of two rye products which can serve as concentrated sources of dietary fibre low in available saccharides.

The effects of Nordic Walking training on selected upper-body muscle groups in female-office workers: A randomized trial

BACKGROUND

Regular Nordic Walking training could improve fitness and reduce tenderness in selected muscle groups in office workers.

OBJECTIVE

An assessment of the effects of a 12-week Nordic Walking training program on the perceived pain threshold (PPT) and the flexibility of selected upper-body muscle groups in postmenopausal female office workers.

METHODS

39 office workers were selected at random for the treatment group (NWg, n = 20) and the control group (Cg, n = 19). The persons from the NW group completed a 12-week Nordic Walking training program (3 times a week/1 hour). PPTs measurements in selected muscles and functional tests evaluating upper-body flexibility (Back Scratch - BS) were carried out twice in every participant of the study: before and after the training program.

RESULTS

A significant increase in PPT (kg/cm2) was observed in the following muscles in the NW group only: upper trapezius (from 1,32 kg/cm2 to 1,99 kg/cm2), mid trapezius (from 2,92 kg/cm2 to 3,30 kg/cm2), latissimus dorsi (from 1,66 kg/cm2 to 2,21 kg/cm2) and infraspinatus (from 1,63 kg/cm2 to 2,93 kg/cm2). Moreover, a significant improvement in the BS test was noted in the NW group compared with the control group (from -1,16±5,7 cm to 2,18±5,1 cm in the NW group vs from -2,52±6,1 to -2,92±6,2 in the control group).

CONCLUSIONS

A 12-week Nordic Walking training routine improves shoulder mobility and reduces tenderness in the following muscles: trapezius pars descendens and middle trapezius, infraspinatus and latissimus dorsi, in female office workers.

Influence of 12-week Nordic Walking training on biomarkers of endothelial function in healthy postmenopausal women

BACKGROUND

The aim of this study was to evaluate the effects of a 12-week Nordic Walking (NW) intervention on nitric oxide synthase activity (eNOS), levels of antibodies against oxidatively modified low-density lipoproteins (oLAb), plasma antioxidant capacity (TAC), thiobarbituric acid reactive substance (TBARS) concentration, carbohydrate and lipid metabolism, and atherosclerosis risk factors (AIP) in postmenopausal women.

METHODS

A sample of 39 women, divided into two comparable groups: training (N.=20) and control (N.=19), took part in the study. Participants in the training group performed a 12-week supervised NW training: 60-minute sessions of exercise, repeated three times per week. The biochemical and anthropometric data were obtained before and after the intervention. During the first and the last training sessions, the individual walking distance in trained group was measured.

RESULTS

After the intervention, significant differences in covered distance, body mass, BMI, fat mass, insulin level (P<0.01), systolic blood pressure and TBARS concentration (P<0.05) were found in trained women.

CONCLUSIONS

Applied training was able to improve functional capacity and body composition in healthy postmenopausal women. It appears to be no direct link between a significant decrease in the level of systolic blood pressure, the level of eNOS activity, TAC, oLAb and plasma TBARS concentration in trained women. It seems probable that NW training would be more effective for postmenopausal women with more severely impaired endothelial function.

Effect of aerobic exercise on insulin, insulin-like growth factor-1 and insulin-like growth factor binding protein-3 in overweight and obese postmenopausal women

AIM

The purpose of presented study was to verify the influence of aerobic physical activity program on the serum insulin, insulin-like growth factor-1 (IGF-1) and insulin-like growth factor binding protein-3 (IGFBP-3) concentrations in overweight and obese postmenopausal women.

METHODS

Somatic parameters and serum concentrations of insulin, IGF-1 and IGFBP-3 were measured in 21 overweight and obese women, before and after 8-week cycloergometer physical workout and 16 age-matched, controls. Age of all studied women ranged from 54 to 78 years.

RESULTS

The comparative analysis of biochemical indices measured before and after the training program showed that the systematic exercise cause the significant decrease in insulin (P<0.05) and IGF-1 concentrations (P<0.05). There were no differences in these parameters in controls over the studied period. The level of IGFBP-3 was not significantly changed in both investigated groups. In women participating in the training program the positive correlation (P<0.05) between changes in IGF-1 levels (Δ) and changes in insulin concentrations (Δ) within two terms of the study were found. The magnitude of changes (Δ) in insulin and IGF-1 levels over the study period correlated with their concentrations measured before the training program (P<0.01).

CONCLUSION

Results of the present study indicate that regular aerobic physical activity decreases serum insulin and IGF-1 levels in postmenopausal women. The magnitude of insulin and IGF-1 concentration changes depend on their initial levels. Changes of IGF-1 levels are associated with insulin concentration modifications.

Assessment of respiratory function in girls with scoliosis after thoracoplasty

BACKGROUND

The aim of the study was to assess pulmonary function in patients after spinal fusion combined with thoracoplasty in comparison with subjects in whom thoracoplasty was not performed, but who underwent intensive rehabilitation. MATERIAL NA DMETHODS: The study population consisted of two groups of adolescent girls about two years after surgical correction of scoliosis by Cotrel-Dubousset method. The subjects in the first group (thoracoplasty group) underwent spinal fusion in combination with thoracoplasty, which consisted in subperiosteal resection of deformed segments of six ribs on top of the rib hump. Patients in the second group (rehabilitation group) had no thoracoplasty, but participated in a 4-week rehabilitation programme based on endurance training. Pulmonary function was assessed in all subjects with resting spirometry. Additionally, maximal oxygen uptake was determined using an indirect method.

RESULTS

Spirometric parameters at rest were significantly higher in subjects participating in the rehabilitation program compared to the thoracoplasty patients. VO2max values were similar in both groups, indicating relatively good exercise capacity.

CONCLUSIONS

Comprehensive motor rehabilitation based on endurance training has a favorable influence on pulmonary function in patients after surgical correction of scoliosis. A rehabilitation program should be included in the management of patients after spinal fusion combined with thoracoplasty.

Response of oxidative stress markers and antioxidant parameters to an 8-week aerobic physical activity program in healthy, postmenopausal women

The aim of the study was to assess the influence of an 8-week aerobic physical activity program on oxidative stress markers, antioxidant parameters, and selected metabolic parameters in healthy, postmenopausal women. The study was carried out in a group of 41 healthy women (mean age 65 years) participating in an 8-week cycle ergometer physical workout of moderate intensity. Before and after completing the training program, the following parameters were assessed: total antioxidant status (TAS) and concentrations of thiobarbituric acid reactive substances (TBARS) in plasma, serum levels of antibodies against oxidatively modified low-density lipoproteins (LDL) (oLAB), serum concentrations of glucose, high-density lipoprotein cholesterol (HDL-C), triglycerides (TG), insulin, and reduced glutathione (GSH) concentrations in red blood cells (RBC). Atherogenic index of plasma (AIP) and insulin resistance index (HOMA(IR)) were calculated. The 8-week aerobic physical activity program resulted in significant decrease (p<0.01) in serum glucose and LDL-cholesterol (LDL-C) levels, plasma TBARS concentrations (p<0.05), and in significant decrease of HOMA(IR) (p<0.01). TAS of plasma and GSH concentrations in RBC increased significantly (p<0.01) over the study period. The results show that an 8-week aerobic training enhanced insulin sensitivity, and improved the balance between oxidants and antioxidants in healthy, postmenopausal women.