## 3 Results
### Differences of Anthropometric and Physical Fitness Measurements among Different Age Groups and Sex
Figure 2: Differences of specific throwing performance for adolescent throwers * \(p\) < 0.05; **\(p\) < 0.01. Correlations between Anthropometric Parameters, Physical Fitness Performance and Specific Throwing Strength  
Associations of anthropometric measurements and physical fitness performance for different boys and girls show a varied degree in Figure 3. More precisely, the Body Mass (r = 0.16, \(p<0.05\)), lower body flexibility (r = 0.23, \(p<0.01\)), hexagon agility test (r = \(-\)0.49, \(p<0.01\)), standing long jump (r = 0.28, \(p<0.01\)) and standing triple jump (r = 0.30, \(p<0.01\)) of boys are significantly correlated with age, while other attributes are unrelated to age. For girls, only the hexagon agility test (r = \(-\)0.29, \(p<0.01\)), standing triple jump (r = 0.22, \(p<0.05\)), and plank test (r = 0.20, \(p<0.05\)) show a correlation with age. Regardless of gender, most physical fitness abilities exhibit significant intercorrelations. Furthermore, associations of different measurements for shot put, discus throw, javelin throw and hammer throw athletes are shown in Figure 4, respectively. Height (in shot put (r = 0.41, \(p<0.01\)), javelin (r = 0.44, \(p<0.01\)), and discus throw (r = 0.47, \(p<0.01\))), weight (in shot put (r = 0.33, \(p<0.01\)), javelin (r = 0.53, \(p<0.01\)), and discus throw (r = 0.56, \(p<0.01\))), and throwing distance are positively correlated; standing long jump (in shot put (r = 0.58, \(p<0.01\)), javelin (r = 0.62, \(p<0.01\)), and discus (r = 0.55, \(p<0.01\))) and standing triple jump (in shot put (r = 0.54, \(p<0.01\)), javelin (r = 0.62, \(p<0.01\)), and discus (r = 0.65, \(p<0.01\))) show a high correlation with throwing distance; 30 m (in shot put (r = \(-\)0.49, \(p<0.01\)), javelin (r = \(-\)0.43, \(p<0.01\)), and discus (r = \(-\)0.58, \(p<0.01\))); and 60 m (in shot put (r = \(-\)0.56, \(p<0.01\)), javelin (r = \(-\)0.65, \(p<0.01\)), and discus (r = \(-\)0.45, \(p<0.01\))) sprits are negatively correlated with throwing distance height, indicating that faster running results in better performance. But no correlation was found between the hammer throw and jumping or sprinting. A negative correlation was found between agility and throwing distance, only in javelin (r = \(-\)0.30, \(p<0.05\)) and discus (r = \(-\)0.40, \(p<0.05\)). Special throwing has a high correlation with FOMB (r = 0.62, \(p<0.01\), in shot put; r = 0.53, \(p<0.01\), in javelin throw; r = 0.60, \(p<0.01\), in discus throw) and BOST (r = 0.74, \(p<0.01\), in shot put; r = 0.62, \(p<0.01\), in javelin throw; r = 0.70, \(p<0.01\), in discus throw). Finally, the gender, age, all anthropometric and physical fitness variables and specific throwing indicators were inserted in the stepwise regression model (Table 3). The results of regression equations indicated that, due to the differences of sport discipline, body morphology and physical fitness have different significant contributor to the final performance (\(p<0.05\) in four throwing events). However, with the exception of the hammer throw, BOST is included in the equation for all. Figure 3: Correlations between anthropometric measurements and physical fitness performance: (a) Boys; (b) Girls. * \(p<0.05\); ** \(p<0.01\). **