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Yayın Age-related reduction in oxygen uptake and ventilatory markers among middle-aged adults(Edizioni Minerva Medica, 2025) Amer Radhi, Mohammed; Shahidi, Seyed Houtan; Çatak, Tuba; Alhusaen Aga, Mohamed T.BACKGROUND: The objective of this research was to investigate age-related variations in crucial physiological indicators such as relative and absolute VO2, aerobic and anaerobic thresholds, and ventilatory dynamics (VT1 and VT2), across six decades of adulthood, specifically spanning from 20 to 60 years. The objective of this study was to measure the extent to which these markers decrease with age and to assess their possible health consequences. METHODS: The study involved 50 individuals who were divided into four distinct age brackets: 20-30, 30-40, 40-50, and 50-60 years. Physiological data were examined using a combination of parametric statistical tests (ANOVA, Tukey honest significant difference [HSD]) and nonparametric techniques (Kruskal-Wallis). Trends in VO2, threshold behavior, and ventilatory responses were assessed using effect sizes, stepwise comparisons, biexponential modeling, and 95% confidence intervals. RESULTS: The results show a substantial decrease in relative VO2 with increasing age, demonstrating a significant decline (P<0.001) that corresponds to a medium effect size (η²=0.213) and a notable reduction of 35% between the youngest and oldest groups. Participants over the age reached ventilatory thresholds (VT1 and VT2) at lower oxygen usage levels, suggesting decreased aerobic capacity. Absolute VO2 and threshold values declined, but only relative VO2 and weight differences demonstrated statistically significant changes. CONCLUSIONS: Research indicates a significant decrease in cardiovascular and respiratory capacity as people age, notably in relative VO2 and ventilatory thresholds, resulting in the onset of fatigue at an earlier stage and a reduction in an individual’s ability to exercise. Early intervention through tailored aerobic training is crucial for countering performance degradation and decreasing cardiometabolic risk in older individuals, as highlighted by these physiological changes.Yayın Assessing aerobic and anaerobic thresholds with emphasis on isocapnic buffering in endurance runners(Western Kentucky University, 2025) Fathi, Yahya Mudhafar; Shahidi, Seyed Houtan; Alhusaen Aga, Mohamed Twfeq OthmanAccurate determination of metabolic thresholds is essential for designing effective endurance training. This study aimed to apply a multi-visit Step–Ramp–Step (SRS) protocol to identify aerobic (VT1) and anaerobic (VT2/RCP) thresholds in trained endurance runners, with a particular focus on delineating the isocapnic buffering region—the ventilatory phase between VT1 and VT2 where carbon dioxide (PetCO₂) remains stable despite rising ventilation. Twelve trained male runners (mean age: 27.1 ± 1.9 years; VO₂max: 60.5 ± 2.1 ml·kg⁻¹·min⁻¹) completed the SRS protocol across separate lab visits. Each session included a 4-minute moderate-intensity phase, a progressive ramp to volitional exhaustion, and a 4-minute heavy-intensity step following a 30-minute recovery. Breath-by-breath gas exchange data (VO₂, VCO₂, VE, RER, PetO₂, PetCO₂) were analyzed using 20-second smoothing. Results showed that VT1 and RCP occurred at 73.2 ± 4.1% and 89.6 ± 3.8% of VO₂max, respectively. The isocapnic buffering zone spanned ~16.4% of the VO₂max range. Unlike previous SRS studies focused on cycling, this study uniquely applies the protocol to running and specifically quantifies the buffering region. These findings support the use of SRS running protocols for efficient, individualized assessment of metabolic transitions in endurance athletes.Yayın Assessing lactate stability at the minimum lactate steady state velocity in male trained middle-distance runners(Public Library of Science, 2026) Shahidi, Seyed HoutanObjectives This study investigated the physiological behavior of the running velocity associated with the Minimum Lactate Steady State (vMLaSS), derived from a 6×800-m interval protocol, and examined whether this intensity produced stable metabolic and lactate responses during a 30-minute constant-load validation run in trained endurance runners. Methods Fifteen trained male middle- and long-distance runners completed a graded treadmill test to determine maximal oxygen uptake. Following a supramaximal sprint to induce hyperlactatemia, each athlete performed a 30-minute constant-load run at a velocity derived from the lactate-minimum approach. Following a supramaximal sprint to induce hyperlactatemia, each athlete performed a 30-minute constant-speed run at their individually determined MLaSS velocity. Blood lactate samples were collected at 10-minute intervals, and breath-by-breath cardiopulmonary variables were continuously recorded. Lactate kinetics were analyzed using a Friedman test with Wilcoxon signed-rank post-hoc comparisons (p<0.05). Results Blood lactate exhibited significant time-dependent fluctuations during the 30-minute trial (Friedman χ2 (3) = 28.72, p<0.001). Lactate increased sharply by minute 10, declined at minute 20, and rose again at minute 30, exceeding the classical MLSS criterion of ≤1 mmol·L-1 change during the final 20 minutes. In contrast, cardiopulmonary variables remained stable throughout VȮ2 (3.43±0.11 L·min-1; p=0.86) and VĊO2 (3.21±0.14 L·min-1; p=0.91). Carbohydrate oxidation predominated (214.5±19.3 g·h-1), whereas fat oxidation remained minimal (–0.9±2.7 g·h-1). Conclusion Despite stable cardiorespiratory and substrate-utilization profiles, the significant variability in blood lactate concentration during the 30-minute constant-load run indicates that the running velocity derived from the lactate-minimum approach did not elicit a lactate steady state in this trained cohort. These findings suggest that physiological responses at the MLaSS-derived intensity may differ from classical steady-state expectations in highly trained endurance runners and highlight the need for direct MLSS verification in future studies.Yayın Comparative analysis of the effectiveness of teaching strategies on students’ physical fitness in physical education lessons(Campus EDUCA SPORTIS S.L., 2025) Derbali, Chawki; Shahidi, Seyed HoutanEffective teaching methods in physical education is crucial for achieving positive outcomes, nonetheless research on the impact of evolving strategies remains limited. This study compares three physical education teaching strategies among Tunisian secondary students, focusing on their impact on physical fitness. The current research employed a reflective observational design over three school trimesters, each implementing a distinct teaching strategy: controlled, motivational, and creative. Physical fitness indicators was assessed using six indicators (BMI, flexibility, vertical jump, shuttle run, long jump, push-ups) and analyzed with a mixed ANOVA model. In 2024, 67 students (32 boys, 35 girls) and aged between16and 18yearscompleted sixphysical fitness tests. Significant differences were found in the overall training effectiveness for all students across vertical jump (p < 0.001, η² = 0.183), flexibility (p < 0.001, η² = 0.028), and 10 x 5m shuttle run (p < 0.001, η² = 0.033). Post-hoc analyses revealed that creative teaching was the most effective strategy for improving physical fitness, while motivational teaching was less effective, especially in showing poorer results in improving shuttle run performance. Gender-specific analysis revealed significant effects for flexibility(p < 0.001, η² = 0.026) in girls and push-ups (p < 0.001, η² = 0.030) in boys, with creative teaching again yielding superior results in these areas compared to other strategies. Finally, these findings show that motivational teaching encourages behavior, controlled teaching relies on oversight, and creative teaching fosters innovation and creativity. Advanced teaching strategies should tailor interventions to diverse fitness outcomes and individual behaviors.Yayın Gender-specific physiological profiles and performance metrics in young elite table tennis players(Kadir Yıldız, 2024) Bilal, Afaf Munther Dawood; Shahidi, Seyed HoutanTable tennis requires a combination of anaerobic and aerobic energy systems, agility, short reaction times, and precise motor skills. The aim of this study is to investigate gender-specific physiological profiles and performance measures in young elite table tennis players. The objectives are to identify key physical and anthropometric attributes contributing to table tennis performance, compare these attributes between male and female athletes, and develop targeted training recommendations. The study involved sixteen players (8 males and 8 females) within the age range of 10 to 18 years who train regularly at Istanbul Pendik Sports Hall. Inclusion criteria required training at least three times per week and participating at championship levels. Anthropometric measurements were taken using a Seca 220R stadiometer and a Seca 710R weighing scale, with body fat percentage estimated via a Tanita scale. Performance tests included vertical jump height (Witty Microgate device), reaction times (custom device), and heart rates (Activio Sport System). Assessments were carried out between 4:00 PM and 6:00 PM. Male athletes had higher mean values in height (159.00 ± 13.29 cm), weight (50.00 ± 12.06 kg), and vertical jump height, whereas female athletes had better reaction times (1.17 ± 0.14 seconds). No statistically significant differences were found in body fat percentage and mean heart rate. t-Tests revealed that gender differences in most performance metrics were not statistically significant, but correlation analysis showed statistically significant relationships between various physical characteristics and performance outcomes (p<0.05). As a result, physical fitness and reaction time are crucial for table tennis performance. Tailored training programs should focus on these attributes to enhance performance in young elite players. Future studies should follow these metrics longitudinally to understand their impact on competitive success.Yayın How has the COVID-19 lockdown affected children's physical activity behaviours?(Springernature, 2023) Shahidi, Seyed Houtan; Aghababa, Alireza; Taşkıran, Mehmet Yavuz; Hassani, FahimehThe implementation of COVID-19 restrictions impacted the day-to-day lives of individuals and their ability to participate in regular community activities; this has led to a decrease in the physical activity of people of all ages, but particularly of children and adolescents. The aim of this study was to investigate physical activity (PA) and mood behaviours in children before and during COVID-19 in Iran. In this study, self-rating questionnaires covering former and current PA patterns and mood were used to collect data on 2047 children. The data collected show the comparisons between levels of PA before and during COVID-19; the duration and intensity of PA in this period varied significantly in both girls and boys. The mood between genders during COVID-19 showed that there was no significant difference. Finally, it should be mentioned that the type of PA plays an important role in the activity of people in these conditions.Yayın Kinesis and pilates for improvement of muscle strength and endurance in middle-aged papulations: a randomized controlled trial(Istanbul Gedik University, 2023) Çeçen, Emre; Taşkıran, Mehmet; Shahidi, Seyed HoutanThe study aims to evaluate two different functional exercises, Pilates and Kinesis. A total of twenty-two women (age 39.59 ± 3.12; weight 62.45 ± 6.20; height 164.41 ± 8.86; mean ± SD) who did not participate in any regular physical activity participated in this study. Participants were randomly assigned to Pilates (n=11) and Kinesis (n=11) groups. In the Kinesis group, training was performed in the vertical plane, and in the Reformer Pilates exercises, training was performed in the horizontal plane. The training was conducted twice a week for eight weeks. The results show a significant improvement in both groups' upper and lower body and core strength and endurance. The current study suggests that the two different methods of functional training are more enjoyable and comfortable for people with no sporting experience.Yayın Lactate kinetics and fatigue dynamics in elite taekwondo athletes during a 30-second continuous jump protocol(Projack, 2025) Kaya, Mehmet Zeki; Shahidi, Seyed HoutanBackground: This study examines lactate kinetics and performance declines during a 30- second BOSCO jump protocol in elite Taekwondo athletes, providing insights into anaerobic performance and recovery. Methods: Anthropometric data, including age, height, and weight, were collected, with averages of 21.2 years (+/- 2.0), 181.4 cm (+/- 4.8), and 70.6 kg (+/- 4.3). Fatigue-induced changes were assessed by measuring jump heights, contact times, and power outputs using the Witty Jump Mat (Italy) during the first and last 5 seconds of the protocol. Blood lactate concentrations were measured with the Lactate Scout 4 (Germany) at baseline, immediately postexercise, and at 3, 6, and 9 minutes post-exercise. Results: Significant declines were observed in jump height (mean decrease = 13%, p = 0.01) and power output (mean decrease = 15%, p = 0.02), alongside an increase in contact time (mean increase = 18%, p = 0.03), reflecting the impact of fatigue on explosive performance. Athlete B showed the greatest reduction in jump height (31.36%), revealing notable inter-individual variability in fatigue resilience. Blood lactate levels increased significantly from baseline (mean = 0.78 +/- 0.08 mmol/L) to peak post-exercise (mean = 3.16 +/- 1.19 mmol/L, p < 0.001) and subsequently declined. Lactate clearance rates were calculated as 40.5% at 3 minutes, 60.5% at 6 minutes, and 65.5% at 9 minutes post-exercise. Athlete D exhibited the fastest clearance rate (72%, p = 0.02), while Athlete C demonstrated delayed recovery. Conclusions: The findings underscore the need for tailored conditioning programs to optimize anaerobic performance and recovery in Taekwondo athletes. Future research should explore the effects of targeted training on anaerobic capacity and competition readiness in combat sports.Yayın Physical activity and health profile of Turkey’s populations “problems and solutions”(Istanbul Gedik University, 2022) Shahidi, Seyed Houtan; Doğan, Satı; Kingsley, J. Derek; Taşkıran, Mehmet YavuzObjectives: Today, the attention of all developed and developing countries is on the issue of the physical and mental health of the people of each country. Because of this, scientific people have defined different solutions and programs. One of these explanations is to clarify guidelines for daily regular physical activity. Therefore, the World Health Organization (WHO) has stated that anyone with any physical ability and disability should be completing physical activities as much as possible. Consequently, in the present study, we aimed to understand the amount of participation in physical activity and the health profile of Turkish populations. We hypothesized that the people who live in Istanbul, Turkey have a low amount of physical activity during the day. Material and Methods: The sample size was 1091 adults (M ± SD; aged: 26 ± 10 years; height: 172.34 ± 10.35 cm; weight: 71.51 ± 14.82 kg, body mass index (BMI): 23.9 ± 3.83 kg/m2;), included both genders. The study also included individuals from both rural and urban districts and from different sociodemographic backgrounds. Thus, during the face-to-face interview, people were asked for information such as participation in physical activity, type of physical activity, smoking, and drinking alcohol. Results: The results of the current study show that, unfortunately, the rate of individuals who participate in physical activity is very low and this rate is lower in women than men. Likewise, as previous studies have shown, smoking has a very high rate among young people. Conclusion: Therefore, according to the results of the present study, it can be concluded that a solution should be considered. Culture related to physical activity and a healthy lifestyle should be created for people who can at home, at work, and in open spaces without any financial cost, or only with tools that can find at home to meet the guidelines regarding physical activity levels.Yayın Redefining endurance testing in soccer: the reliability and impact of a ball-integrated yo-yo intermittent recovery test(Campus Educa Sportis S.L., 2025) Yılmaz, Levent; Shahidi, Seyed HoutanThe Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo) is a widely recognized method for assessing aerobic capacity in soccer players. Despite its utility, the test does not incorporate ball manipulation, which is a critical component of soccer-specific endurance. This study aimed to evaluate the reliability of a modified soccer-specific Yo-Yo test (MYo-Yo) that includes ball dribbling, passing, and control, and to compare the physiological responses with those from the conventional Yo-Yo test. Twenty elite male soccer players (mean ± SD: age, 16.4 ± 1 years; height, 173 ± 7 cm; body mass, 65.7 ± 10.4 kg) completed both Yo-Yo tests, with and without ball manipulation. Performance metrics included the number of completed shuttles (Level), total distance covered (Distance; m), and blood lactate concentration (Lactate; mmol/L), while maximal oxygen consumption (V̇ O2 max; ml/min/kg) was estimated for all trials. The modified Yo-Yo test (MYo-Yo) demonstrated high reliability, with Intraclass Correlation Coefficients (ICC) of 0.802 for Level, 0.982 for Distance, 0.997 for V̇ O2 max, and 0.992 for Lactate (P ≤ 0.001). Comparatively, the MYo-Yo test resulted in significantly lower distances than the standard Yo-Yo test (832 vs. 1520 m, respectively; P < 0.001) and lower lactate concentrations (5.2 vs. 10.9 mmol/L; P < 0.001). No significant correlations were found between the two tests for outcomes (P > 0.05). In summary, integrating ball manipulation in the MYo-Yo test introduces distinct physical and technical demands that influence overall performance. The MYo-Yo test offers a reliable alternative for assessing soccer-specific endurance, better replicating the physical demands encountered during a soccer match.Yayın Talent identification pathway “coaches, family, and environment eyes”(Istanbul Gedik University, 2022) Shahidi, Seyed Houtan; Kıngsley, J. Derek; Taşkıran, Mehmet YavuzTalent identification in sport is a complex way that needs a lot of knowledge to be understood. So, in the talent identification road, there is a different and important parameter that leads the coaches to be precise in this way. For example, if look at 50 years ago the researchers just focused on genetic and performance parameters. However, today’s vision of talent identification is completely different, and many researchers note that are sure whether talent exists or not. Besides genetics and performance, there are other factors that affect selection. For instance, where the child is born and grows also who is the coach that trains him/her? With a little bit, of an open eye and thinking on this topic understood that above mention topics are vital for the selection or deselection of the child into the sport. Besides, in this way, there are other components. First of all, maturity and growth which is the most but not the last parameter. Maturity is related that if the child has a normal maturity or if he/she has an early or late. Due to this, many of the team coaches are looking to find a child who has an early maturation, he/she has some advantages compared to peers. So, early matured are heavier, and bigger and taller. That’s why the authors try to clearly note that talent identification is very difficult and it is like swimming in the ocean without any direction. So, the coaches need to be more sensitive in this path.Yayın The effectiveness of sprint athletes in removing lactate after reaching maximum effort(Edizioni Minerva Medica, 2026) Tahiroğlu, Ferdi; Shahidi, Seyed HoutanBackground. This investigation sought to investigate the time-dependent changes in blood lactate levels and oxygen intake (VO2) after maximal sprint efforts in elite 100-m sprinters, with an emphasis on recovery rates and their relevance to performance tactics for sprinters. This research provides a comprehensive analysis of metabolic recovery patterns within this underrepresented athletic group through the application of a bi-exponential model. Methods. Twenty elite 100-meter sprinters underwent a graded exercise test and a 30-second Wingate Anaerobic Test as part of the methods. Measurements of blood lactate levels were taken at three specific points: at the start of exercise, immediately after exercise, and at various intervals of up to 20 minutes following exercise. Oxygen consumption was tracked in real-time throughout and following the GXT. Results. Typically, peak blood lactate levels of 14.9 +/- 3.5 mmol/L were attained at 3 minutes following exercise. The rate at which lactate is cleared from the body occurs in two distinct stages. The first stage was a quick process (lasting around 60 seconds), and the second stage was much slower (taking approximately 300 seconds). The recovery of VO2 also showed a bi-exponential pattern, with time constants associated with quick phosphocreatine resynthesis and prolonged oxidative recovery. Average peak VO2 levels measured 45.4 +/- 4.1 mL & centerdot;kg(-1)& centerdot;min(-1), which matches what is typically seen in trained athletes. A sophisticated modelling method uncovered detailed patterns of recovery for individual athletes, suggesting ways to fine-tune rest breaks and track fatigue levels during sprint training, which specifically involves post-exertion exhaustion. Conclusions. The research offers new findings on the rates of lactate removal and oxygen usage recovery in top-level sprinters by combining longer data collection periods and a two-stage mathematical analysis. These findings may suggest implementing more tailored recovery plans in sprint training and contribute to the increasing acknowledgment of VO2 kinetics as an indicator of both performance and physical durability.Yayın Training wiser instead of training harder: a Complex Training Program (CPX)(Istanbul Gedik University, 2021) Shahidi, Seyed Houtan; Kingsley, J. Derek; Svensson, Michael; Taşkıran, Mehmet Yavuz; Hasssani, FahimehA Badminton competition at the elite level requires a high combination of neuromuscular function and the involvement of these systems depends on the nature of the sport. This mini-review study aimed to discuss the impact and vital role of complex training programs (CPX) on physiological performance variables. CPX training program is one of the most advanced forms of the sports training program which follows as the combination of traditional weight training exercises immediately with lighter load explosive plyometric exercises, set for set. Previous researchers have shown that the CPX training program has a positive impact on the anthropometric variables, sprint, vertical jump (VJ), and change of direction (COD). The results of the authors recommend the use of CPX to maximize the upper and lower body power. Therefore, many practitioners and coaches are looking to find the best training for optimizing training programs and at the same time reduce the risk of injury. To become an elite badminton athlete, the physiological characteristics requirement is quite specific. Therefore, the authors mentioned that “right training, at the right time, makes you perfect”. In conclusion, this mini-review has revealed that a combination of weight strength training followed by plyometric training is needed during periodization for improving neuromuscular functions.
