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Background: Thalassemia major (TM) is characterized by anemia, and a synthesis defect occurs in both beta globin genes on the short arm of chromosome 11. Thalassemia patients suffer fatigue, and decreases in VO _2max and aerobic exercise capacity are observed. Cardiopulmonary exercise test (CPET) data are valuable for interpreting the responses of the cardiovascular, respiratory, and locomotor systems to exercise. The main purpose of our study was to reveal the effects of transfusion on respiratory parameters, oxygen uptake, the ventilatory threshold, and maximal exercise capacity in the adolescent population. Methods: Twelve boys with TM (age: 16.0 ± 0.6 years) participated in our study. Pulmonary function tests and incremental symptom-limited CPETs on cycle ergometers were performed before and after blood transfusion. Results: The exercise capacity (VO _2max , mL kg ⁻¹ min: 27.3 ± 1.9 vs 30.0 ± 2.1; P < 0.005) and maximal watt value (89.1 ± 5.1 and 101.6 ± 5.5 W; P < 0.001) were increased after transfusion. The changes in ventilatory equivalents and end-tidal CO ₂ - O ₂ partial pressures were compared before and after transfusion at five different stages. These stages are determined as rest (pre), VT, maximum (max) points, and exercise intensities corresponding to 50% of rest and VT (Mid1) and 50% of VT and maximum (Mid2). Compared with transfusion, transfusion significantly reduced the VE/VO ₂ Mid1 and VT values ( P < 0.05). In addition, the VE/VCO ₂ values were significantly lower at Mid1 and VT than before transfusion ( P < 0.05). Conclusions: Although no significant change in the ventilatory threshold was detected after transfusions, the significant decrease in the minute ventilation to oxygen and carbon dioxide ratios may be interpreted as a sign that respiration is more efficient in these patients. The absence of a significant change in the VO ₂ /work rate after transfusion suggests that patients can tolerate an increased workload. The ability of the cardiopulmonary system and skeletal muscle to cope with the increased workload indicates that these systems are not adversely affected in these patients. A well-tailored activity routine may be important to recommend for TM patients to prevent the adverse effects of a sedentary lifestyle, which may threaten their wellness during adulthood.

Purpose: The aim of our study was to compare the thigh muscle strengths between the operated and non-injured legs and to evaluate the hamstring/quadriceps (H/Q) ratios by the isokinetic dynamometer at different angular velocities, in individuals with unilateral interior cruciate ligament (ACL) surgery. Material and Methods: Five female and fifteen male recreational athletes with a single-limb ACL operation within the last 1 year enrolled in the study. After physical examination, thigh circumferences were measured. Isokinetic testing of the hamstring and quadriceps were performed at different angular velocities. Peak torque and H/Q ratio values were evaluated from the isokinetic data, and the relation between leg circumference differences were analyzed. Results: The isokinetic extension and flexion muscle strengths at 60, 180, and 240°/sec (19.4 ± 11.5%, 16.6 ± 13.2%, 17.4 ± 13.2% higher in extension, 17.9 ± 14.5%, 19.7 ± 15.9%, 21.9 ± 17.4% higher in flexion, respectively) and the 10cm and 15cm above the patella circumferences were significantly higher in non-injured leg than operated leg. The extension fatigue index was significantly higher in the non-injured leg(30.6±9.5%) than operated leg (24.7±10.9%). In the operated leg, significant correlation was found between flexion peak torque at 60°/sec and flexion fatigue index. Conclusion: The decreases in peak strengths indicate atrophy of the thigh muscles in the operated leg. The muscle atrophy will lead to imbalance and may cause complications. In the post-operative period, it is important to detect the deficit with an isokinetic dynamometer and organize appropriate treatment protocols at early stages to enable the patient to regain their preoperative health.

Background: Maximal kicking performance relies heavily on the coordinated involvement of the hip flexors and knee extensors, yet exercises that specifically target these muscle groups are rarely prioritized in soccer training regimens. Objective: This study aimed to examine the effects of a leg-kicking exercise program (LKE) on the kicking speed, sprint performance, and agility of young players. Methods: Thirty-nine youth players were randomly assigned to either an LKE group (n = 18; 15.9 ± 0.9 years) or a control group (n = 21; 15.8 ± 0.6 years). The LKE group performed a leg-kicking exercise three days a week. The participants underwent body composition analysis, isometric knee, isokinetic knee and hip strength tests, maximal ball speed, linear sprint, and agility tests at baseline and post-intervention. Results: In the LKE group, muscle mass, maximal ball speed in both legs, and both isometric and isokinetic strength significantly increased (p < 0.05), while agility and sprint performance showed no significant changes (p > 0.05). Conclusion: A 6-week LKE program, in addition to soccer training, may enhance kicking speed in youth players. The LKE may serve as a practical alternative to traditional strength training for improving muscle strength and kicking performance.

Background/Objectives: Telomeres and the enzyme telomerase play essential roles in cellular aging and cardiovascular health. Physical activity is thought to influence telomere dynamics via upregulation of the hTERT gene, which encodes the catalytic subunit of telomerase. However, data on this relationship in middle-aged endurance athletes remain limited. This study aimed to investigate the association between long-term endurance training, cardiac structural adaptations, and hTERT gene expression in middle-aged elite athletes. Methods: A total of 38 middle-aged elite runners and 37 age-matched sedentary controls were enrolled. Echocardiographic assessments, VO₂peak measurements, and hTERT gene expression analysis using RT-PCR were conducted. Left ventricular mass (LVM), wall thicknesses, and cardiac volumes were compared, and correlations with hTERT expression were analyzed. Results: Athletes demonstrated significantly higher VO₂peak and echocardiographic parameters including LVEDD, LV mass, and wall thicknesses (p < 0.05). hTERT gene expression was 2.06-fold higher in athletes compared to controls. Significant positive correlations were observed between hTERT expression and VO₂peak, LVM, LV wall thicknesses, and right ventricular parameters. Conclusions: These findings suggest that regular aerobic exercise may contribute to both improved cardiovascular performance and cellular longevity by enhancing telomerase-related mechanisms.

Hemiplegia is characterized by neuromuscular dysfunction that disrupts the patient’s quality of life and daily activities. Gait disorders can be observed in post-stroke hemiplegic patients. In addition to neurological and physical therapy approaches, individually prepared isokinetic exercises help the patient return to normal life. A 38-year-old patient with right-sided post-stroke hemiplegia was enrolled in a 4-week lower extremity exercise program specific to his current condition using an isokinetic dynamometer.Due to the 4-week lower extremity strengthening program, there was an increase in quadriceps and hamstring muscle strength and body muscle mass. According to the physical activity questionnaire, the patient’s daily activity increased, and it was determined that he could walk 15.4% longer in the 6-minute walk test. Hemiplegic patients can be supported to return to their daily lives and become more active with personalized isokinetic dynamometer muscle-strengthening programs. In addition, it may be possible to prevent or delay the occurrence of many cardiovascular, metabolic, and related diseases that may occur due to sarcopenia and sedentary life.

Introduction Lower limb stiffness has been shown to be associated with running economy (RE) in adults, but this relationship in children remains unclear. Objectives The purpose of this study was to investigate the relationship between lower limb stiffness, RE, and repeated-sprint ability in child soccer players. Methods Twenty-eight male child soccer players (mean age 11.8 ± 0.9 years) participated in the study. RE was determined by measuring the steady-state oxygen uptake (ml/min/kg) at submaximal running speeds of 8 and 9 km/h. Vertical and leg stiffness were calculated from the flight and contact time data obtained during two submaximal running tests. Additionally, vertical stiffness was measured during the maximal and submaximal hopping tests. All participants performed the repeated sprint test consisting of 10 × 20-m all-out sprints interspersed with 20-s active recovery. Results During both submaximal running tests, vertical (r= –0.505 to –0.472) and leg stiffness (r= –0.484 to –0.459) were significantly correlated with RE (p< 0.05). Maximal (r= –0.450) and submaximal hopping stiffness (r= –0.404) were significantly correlated with RE at 8 km/h (p< 0.05). Maximal hopping stiffness was significantly correlated with the best sprint time (r= –0.439) and mean sprint time (r= –0.496) (p< 0.05). Vertical (r= –0.592 to –0.433) and leg stiffness (r= –0.612 to –0.429) at 8 and 9 km/h and submaximal hopping stiffness (r= –0.394) were significantly correlated with the fatigue index (p< 0.05). Conclusions Current findings indicate that the lower limb stiffness may be an important determinant of both RE and repeated-sprint ability in child soccer players. Level of Evidence II; Diagnostic Studies - Investigating a Diagnostic Test.

Amaç: Bu çalışmada sporcu ve sedanter bireylerin performans testleri sonucunda tespit edilen en yüksek yağ yakım aralıkları ve substrat kesişim noktalarındaki metabolik değişkenlerin değerlendirilmesi amaçlanmıştır.Gereç ve Yöntem: Çalışmaya 10 sedanter (22,1 ± 0,5 yıl) ve 11 sporcu (22,3 ± 0,6 yıl) olmak üzere toplam 21 erkek gönüllü katılmıştır. Katılımcıların egzersiz testleri yürüme bandında indirekt kalorimetre kullanılarak yapılmıştır (Cosmed Quark CPET). Uygulanan iki farklı egzersiz testi sonucunda katılımcıların performans düzeylerine ve yağ oksidasyon hızlarına ait veriler elde edilmiştir.Bulgular: Beden kitle indekslerine göre sporcular normal, sedanter bireyler ise fazla kilolu sınıfında yer almışlar ve sedanter bireylerin vücut yüzde yağ oranları sporculara kıyasla istatistiksel olarak anlamlı düzeyde yüksek bulunmuştur. Sporcuların pik oksijen alım seviyeleri anlamlı düzeyde yüksek olmasına karşın, en yüksek yağ oksidasyon hızları sedanter bireylere benzer seviyede tespit edilmiştir. Karbonhidratların baskın enerji kaynağı haline gelmeye başladığı kesişim noktasında, sporcu ve sedanter bireylerin oksijen alım miktarları arasında istatistiksel fark olmamasına karşın, bu değerin maksimal oksijen alım kapasitelerine oranı değerlendirildiğinde sporcu grupta istatistiksel olarak anlamlı düzeyde düşük bulunmuştur. Sonuç: Oksijen alım kapasitesi yüksek olan sporcu bireylerin hem en yüksek yağ yakım hızlarının hem de kesişim noktasındaki yağ yakım hızlarının sedanter gruba kıyasla istatistiksel farklılık göstermemesi, yağ oksidasyonunu belirleyen tek faktörün maksimal aerobik kapasite olmayabileceğini düşündürmektedir.

Amaç: Bu çalışmada, 40 dakikalık sabit submaksimal bir egzersiz sırasında, farklı aerobik kapasiteye sahip sedanter ve sporcu bireylerin maksimal yağ oksidasyon hızlarına ait değişimlerin değerlendirilmesi amaçlanmıştır.Gereç ve Yöntem: Çalışmaya rekreasyonel düzeyde spor yapan (n=11) ve sedanter olan (n=10) toplam 21 erkek katıldı. Katılımcıların egzersiz testleri yürüme bandında (Cosmed), gerçekleştirildi. Yağ oksidasyon hızları ve egzersize verdikleri metabolik cevaplar indirekt kalorimetri ile ölçüldü (Quark CPET). Tüm katılımcılara, maksimal performans testi, yağmaks testi ve 40dk yürüme testi olmak üzere üç farklı test uygulandı.Bulgular: Sporcu gruba ait zirve oksijen tüketim değeri, % yağ ve % kas oranları, beden kitle indeks değeri ve maksimal yağ oksidasyonunun elde edildiği egzersiz şiddet düzeyi ile sedanter gruba ait aynı parametre değerlerinde istatistiksel olarak anlamlı farklılıklar bulundu. Maksimal yağ oksidasyonu değerlerinde ise anlamlı bir farklılık yoktu. Diğer taraftan yağ oksidasyonu 40dk’lık sabit submaksimal egzersiz sırasında sabit kalmayarak her iki grupta da azaldı. Sporcu grupta 16dk, Sedanter grupta yaklaşık 14dk’da sabit bir düzeye ulaştı.Sonuç: Yağ oksidasyonunu belirlemede maksimal aerobik kapasite dışında başka faktörlerin de araştırılmaya devam edilmesi oldukça önemlidir. Daha elit sporcularda yağ oksidasyon paterninin araştırılması yağ metabolizmasındaki farklı fizyolojik mekanizmaların anlaşılmasında katkıda bulunabilir.