Latar belakang: Latihan fisik intensitas tinggi dapat menyebabkan timbulnya stres fisik yang akan menekan sistem imun pada tubuh atlet. Penurunan fungsi sistem imun tersebut akan meningkatkan risiko infeksi dan menurunkan performa atlet. Leukosit adalah komponen yang berperan dalam homeostasis sistem imun. Salah satu faktor yang mempengaruhi sistem imun adalah asupan zat gizi termasuk seng dan zat besi.Tujuan: Untuk mengetahui hubungan tingkat asupan seng dan zat besi dengan jumlah leukosit pada atlet sepak bola remaja.Metode: Penelitian ini merupakan penelitian observasional dengan rancangan Cross sectional. Penelitian dilaksanakan di Sekolah Sepak Bola (SSB) Terang Bangsa Semarang. Jumlah subjek sebanyak 24 atlet remaja dengan metode pengambilan sampel Simple Random Sampling. Data asupan makan diperoleh melalui food recall 24 jam, data aktivitas fisik, kualitas tidur dan kondisi stres psikologis diambil menggunakan kuesioner, dan sampel darah diambil melalui pembuluh darah vena. Data dianalisis menggunakan uji korelasi pearson dan rang spearman.Hasil: Sebanyak 91,7% jumlah leukosit subjek dalam kategori normal. Rerata tingkat asupan seng subjek yaitu 56,22% sedangkan zat besi sebesar 57,7%.Tidak terdapat hubungan signifikan antara  tingkat asupan seng dan zat besi dengan jumlah leukosit.Simpulan: Tidak terdapat hubungan signifikan antara  tingkat asupan seng dan zat besi dengan jumlah leukosit.

Background: Hydration status is a condition that describes total body fluid. One of the method of measuring hydration status is urine specific gravity. Energy density of food is the amount energy content of total weight food. Foods with high energy density tend to have a lower water content, which will affect fluid intake. The aim of this research was to know the correlation of energy density and fluid intake with urine specific gravity as one of the markers of hydration status. Method: This was an observational research with cross-sectional study design. The research was conducted in Senior High School 15 Semarang involving 55 subjects by Simple Random Sampling method. Food intake and fluid intake were assessed by 1x24 hours Food Recall. Urine specific gravity measured in laboratory. Body fat percentage measured by BIA (Bioelectrical Impendance Analysis) and physical activity assessed by 1x24 hours record physical activity. Data were analyzed by rank spearman.Result: Median of urine specific gravity men and women was 1,02 g/ml. Mean of energy density in men was 1,8±0,32 kcal/gram, in women was 2,1±0,59 kkal/gram. Mean of fluid intake in men was 2406,4±491,38 ml, in women was 2159,5±648,42ml. There was significant correlation of fluid intake with hydration status (p=0,027). There was no significant correlation of energy density and hydration status (p=0,218). Multivariate analysis showed that 14,6% of hydration status is affected by both fluid intake and energy intake. Conclusion: There was significant correlation of fluid intake with urine specific gravity. There was no significant correlation of energy density and urine specific gravity.

Latar belakang: Kelelahan otot pada atlet sepak bola dapat memperburuk performa atlet selama pertandingan di lapangan. Kelelahan otot ditandai dengan adanya hasil samping asam laktat. Kadar hemoglobin yang rendah dapat menimbulkan produksi asam laktat yang lebih tinggi.Tujuan: menganalisis hubungan kadar hemoglobin dengan kadar asam laktat atlet sepak bola remaja.Metode: Penelitian observasional dengan desain Cross-sectional di Sekolah Sepak Bola Terang Bangsa Semarang. Sampel penelitian adalah 24 atlet sepak bola berusia 15-17 tahun. Kadar hemoglobin diukur menggunakan metode cyanthemoglobin. Kadar asam laktat diukur dengan cara pengambilan sampel darah kapiler di ujung jari menggunakan alat Roche Accutrend Plus. Uji hubungan dilakukan dengan menggunakan korelasi Pearson dan Rank Spearman.Hasil: Lebih dari 70% subjek memiliki tingkat kecukupan asupan protein yang kurang dan 50% di antaranya juga memiliki tingkat kecukupan asupan zat besi yang kurang. Meskipun demikian, hampir seluruh subjek memiliki kadar hemoglobin yang normal. Uji korelasi menunjukkan adanya hubungan negatif yang signifikan antara kadar hemoglobin dengan kadar asam laktat dengan nilai kekuatan korelasi sedang (p<0,05; r: -0,465). Artinya, jika atlet memiliki kadar Hb yang tinggi, maka dia akan memiliki kadar asam laktat yang rendah, begitupun sebaliknya.Simpulan: Adanya hubungan yang signifikan antara kadar hemoglobin dengan kelelahan otot yang ditandai dengan kadar asam laktat pada atlet sepak bola remaja.

Muscle fatigue in adolescent soccer athletes can degrade performance during a match. A low Glycemic Load (GL) diet before exercise is believed to improve soccer athlete performance because it can decrease carbohydrate oxidation during exercise and has a lower increase in lactic acid levels than a high GL diet. The study aimed to identify the effect of low and high glycemic load diets on muscle fatigue in adolescent soccer athletes. A quasi experimental with multiple series group design was conducted in November 2019 on 22 adolescent soccer athletes aged 15-17 at the Terang Bangsa Soccer School Semarang. The low GL group was given food with GL 9.15; while the high GL group contained GL 27.29. Diets given once in 2 hours before exercise. Each group was triggered by RAST (Running based Anaerobic Sprint Test) to cause anaerobic muscle fatigue. Muscle fatigue is measured using blood lactic acid, BUN (Blood Urea Nitrogen), and fatigue index. There were no significant differences in blood glucose, lactic acid, and BUN levels between the low GL and high GL groups (p>0.05). Nonetheless, a low GL diet had a smaller increase in blood glucose levels (1.91 mg/dL vs 4.09 mg/dL) and lactic acid (4.5 mg/dL vs 4.7 mg/dL) after exercise than high BG diet. A low GL diet also has a lower fatigue index than a high GL. Keyword: glycemic load diet, muscle fatigue, lactic acid, blood urea nitrogen.

High-intensity physical exercise causes physical stress that will suppress immune system in athlete’s body. Decreased immune system function can cause physiological and pathological changes such as fatigue, reduce athlete performance, and increase risk of infection. Regulation diets of glycemic index (GI) and glycemic load (GL) are known to help control blood glucose during exercise so the immune system can be maintained.The purpose of this study was to determine differences effects of low and high glycemic load diets on immune responses in adolescent football athletes. This study was a quasi experimental with multiple time series design, conducted on 22 adolescent football athletes aged 15-17 years old. The subjects were divided into two groups, low GL diet group was given carbohydrate-source foods with GL 9.15, high GL diet group was given foods with GL 27.29. Diet was given once in the morning and 2 hours later subjects doing RAST (Running-based Anaerobic Sprint Test) to trigger physical stress. Immune response was measure using total leukocytes and leukocytes differential count. There were no significant differences in blood glucose levels, leukocyte counts, and leukocytes differential count between low GL and high GL groups (p>0.05). Low GL diet causes an increase in blood glucose and total leukocytes smaller than high GL diet.