## 4 Discussion  
This study was the first to examine differences in anthropometric and fitness measures between class years in Division I female field hockey players. First-year athletes had lower values for the anthropometric measures, mass and percent body fat. First-year athletes also  
Figure 3: Percent change from pre season to post season for each individual player, grouped by class year for (**A**) vertical jump and (**B**) Yo-Yo IR1 distance. had lower vertical jump height and Yo-Yo IR1 distance in accordance with the hypothesis. Additionally, when averaged across all athletes, all measures increased pre to post season. While mass and percent body fat, on average, increased slightly for all class years, the largest gains were seen in the first-year. First-years had the lowest average mass which is different from a study that examined differences in mass in Division I female soccer players [18]. [PERSON] et al. found that their redshift athletes, who were equivalent in experience to the current study's first-years, were not different in mass from the next two grade levels [18]. It should be noted that the soccer measurements were recorded in February and March, three to four months after a competitive season, compared to the pre season data reported in this paper collected in August. Average field hockey mass post season was higher for all equivalent class years than the soccer players. The average mass increase for first-year field hockey athletes of 3.0 kg (4.6%) is slightly higher than the average mass increase for first-year college students. A meta-analysis conducted on 24 studies found a weighted mean of 1.75 kg increase in first-years' (both male and female) mass [33] while a second meta-analysis found an average of 1.34 kg increase in mass for female first-years [34]. The meta-analysis also suggests that the largest gains for mass occur in the first semester of the first-year [34]. Since the field hockey season occurs in the fall, which for first-year students is the first semester of their first year, the increase in mass seen in the first-year athletes may be a result of the combination of the first semester in college and athletic training. First-year percent body fat was comparable to Division II field hockey players reported at 17.29 \(\pm\) 3.79% [15]. The sophomores and juniors, while having a higher percent body fat than the first-year athletes, were lower than elite English field hockey players (23.0 \(\pm\) 1.9%) aged 22.7 \(\pm\) 2.8 years [4] and regional Australian field hockey players (24.8 \(\pm\) 0.7%) aged 19.4 \(\pm\) 1.0 years [5]. While important to consider, direct comparisons to past studies with respect to percent body fat have many challenges. The method of calculating percent body fat was not consistent across all studies. The current study used NIR to measure percent body fat compared to standard calipers in the other studies. The game play is also different between the studies. As stated in the introduction, numerous NCAA rule changes have occurred since the study on Division II players, and international games have different rules from the NCAA. Due to different regulations (e.g., NCAA rules) and player expectations (students, non-students) the training environment also can be very different between levels of play, which cannot be controlled for when comparing results [7]. The degree to which player behavior off the field also can vary. In this study, the athletes had one large group meeting with a nutritionist. Additional individual coaching on nutrition was offered to each subject; however, they were not required to further engage with nutritional coaching and their nutritional activities were not tracked throughout the season. Similarly to body mass, the increase in percent body fat for first year athletes may be due to changes that occur during the first semester in college, such as change in diet, and differences in athletic training compared to sophomores and juniors.