The purpose of this study was to investigate the relationship between low back pain (LBP) any physical characteristics in university wrestlers. We especially focused on radiological abnormalitie (RA) in their lumbar regions.
Physical characteristics and isokinetic trunk muscle strength of the 55 male university wrestlers were measured. MRI was used to evaluate the cross-sectional areas of trunk muscles between lumbar spine 3 and 4 (L3/4) . Evaluations of LBP were based on the diagnose of orthopedic surgeons and the questionnaire test. According to this evaluation, we assigned all wrestlers into two groups as the LOP group and the no LOP group. Furthermore, four groups were defined by having RA based on X-ray and MRI diagnose.
We obtained the following results. In comparison between the LOP group and the no LOP group, the trunk muscle extension flexion strength ratio of the LOP was significantly lower than that of the no LOP group. In addition, the LOP without RA group showed significant low strength of their trunk extensors in comparison with the no LOP without RA group.
We considered that the relative low strength of trunk extensors should have some effect on LBP in university wrestlers.

The purpose of this study was to investigate relationships between low back pain (LBP) and psychological conditions in university wrestlers.
We examined psychological conditions of seventy male university wrestlers using the Psycholo gical Condition Inventory (PCI) test and evaluated whether psychological conditions have some relationships with LBP. Evaluations of LBP were based on a questionnaire test and the diagnosis of orthopedic surgeons. Based on the LBP evaluation, we assigned all wrestlers into two groups as the LBP group and the non-LBP group.
We obtained the following results. There were twenty-eight university wrestlers (40%) in the LBP group and forty-two wrestlers (60%) in the non-LBP group. Wrestlers in the LBP group showed significantly high values in all factors relating to fatigue in comparison to the non-LBP group.
We conclud that the university wrestlers with LBP feel fatigue in their minds and bodies.

To examine risk factors for shoulder injuries with or without history of the injuries using the stratification analysis for collegiate rugby players. 71 elite rugby players from one university rugby club joined in the preseason medical screening related to their shoulder joints, including basic demographics, history of injuries, and physical findings at that time. Subsequently, the occurrence of shoulder injuries was recorded during four playing seasons. Analysis was stratified with or without history of the injuries; player without the past history of injury, 47 players; player with the past history of injury, 24 players. As a result of all players with the past history, 13 players sustained the shoulder injuries. Internal rotational range of motion [IR ROM] (OR, 1.5; 95%CI, 1.13-1.96; p=0.004), external rotational range of motion [ER ROM] (OR, 1.9; 95%CI, 1.21-2.87; p=0.005), horizontal flexion range of motion [HF ROM] (OR, 1.3; 95%CI, 1.03-1.64; p=0.025), IR muscle strength (OR, 0.4; 95%CI, 0.20-0.65; p=0.001) and rugby experience (OR, 1.2; 95%CI, 1.02-1.46; p=0.032) were associated with the shoulder injuries. On the other hand, 10 players sustained injuries of the players without the past history of injury. IR muscle strength (OR, 0.3; 95%CI, 0.11-0.72; p=0.008) and rugby experience (OR, 1.4; 95%CI, 1.11-1.66; p=0.003) were associated with the shoulder injuries. This study clearly showed that IR, ER, HF ROM, IR muscle strength and rugby experience were important initial risk factors for shoulder injuries. Moreover, IR muscle strength and rugby experience were important recurrence risk factors for shoulder injuries.

The purpose of this study was to clarify physical characteristics related to low back pain (LBP) in collegiate track and field athletes. We particularly focused on the nature of the track and field. The subjects were 21 male collegiate track and field athletes including only sprinters, hurdlers, long jumpers and triple jumpers. The examined parameters were physical characteristics, isokinetic flexor and extensor strength in the knee and trunk regions. The evaluation of LBP was estimated by a questionnaire test and orthopedic surgeons' diagnosis. According to these evaluations, we divided all track and field athletes into two groups ; LBP group (n＝11, 52.4%) and no LBP group (n＝10, 47.6%). As a result, a take-off leg of knee flexor/extensor strength ratio in the LBP group was significantly lower than that in the no LBP group (P＜0.05). The LBP group showed a significant difference between a take-off leg and a lead leg in knee flexor strength compared with the no LBP group (P＜0.05). The LBP group has been short engaged in the track and field than the no LBP group (P＜0.05). In the trunk flexor and extensor strength, there was no significant difference between the LBP and the no LBP group in this study. These results suggest that the imbalanced knee muscle strength may be one of some factors related to chronic low back pain in collegiate track and field athletes.