Effect of Force Sense to Active Joint Position Sense and Relationships between Active Joint Position Sense, Force Sense, Jumping and Muscle Strength

Effects of contrast water therapy on proprioception of the knee joint and degree of fatigue in sprinters after high intensity training

OBJECTIVE

To investigate the effect of contrast water therapy on proprioception of the knee joint and indicators associated with fatigue in sprinters after high intensity training.

METHODS

A total of 40 sprinters were selected and divided into an observation group and a control group. The observation group got 14 minutes of contrast water therapy, while the control group took 14 minutes of sitting rest after training. The knee position sense, muscle force sense, joint reaction angle to release, knee joint function, and indictors associated with fatigue were evaluated before and after exercise at different time points.

RESULTS

At 24 h, 48 h, and 72 h after exercise, the active position sense and muscle force sense of the control group were significantly lower than those of the observation group (all P<0.05). At 48 h after exercise, the passive position sense of the control group was significantly lower than that of the observation group (all P<0.05). At 24 h and 48 h after exercise, the joint reaction angle to release of the control group was significantly greater than that of the observation group (all P<0.05). Additionally, the IKDC2000 and Lysholm scores after interference in the observation group were greater than those of the control group (all P<0.05). The indicators associated with fatigue after interference in the observation group were significantly lower than those of the control group (all P<0.05).

CONCLUSION

Contrast water therapy can effectively alleviate muscle force sense, promote muscle proprioception, improve knee joint function, and enhance recovery from fatigue.

Reference value of knee position sense in weight-bearing and non-weight-bearing conditions

BACKGROUND

Our study aimed to identify age-related changes in knee proprioception to provide reference values for weight-bearing (WB) and non-weight-bearing (NWB) conditions and to identify factors (age, WB condition, dominance, and sex) that can affect knee proprioception.

METHODS

A total of 84 healthy adult men and women were recruited. Active knee joint position sense (JPS) was measured using a digital inclinometer for knee proprioception. The participants performed the required movements actively, with verbal feedback from the examiner, slowly moving to the target angles (30° and 50°) and maintaining them for 5 s before returning to the starting position. Afterward, without assistance from the examiner, the participants actively moved back to the same angle, and the examiner confirmed the angles. This procedure was repeated twice for each target angle, and the average values were used as the data. The participants were barefoot, wearing shorts, and closed their eyes while the measurements were obtained. The measurements were first obtained on the dominant side under the NWB conditions. When a change in posture was needed during the measurement, the participants sat in a resting position for 2 min.

RESULTS

Except for age, all other factors (WB condition, dominance, sex) were not statistically significant. Age showed a significant difference in knee JPS, except for the non-dominant side at 30° and the dominant side at 50° in the NWB condition.

CONCLUSION

This study indicates that the WB condition, dominant side, and sex need not be considered when measuring and assessing knee JPS. Age shows a negative correlation with knee joint position sense, and the reference values presented in this study can be used as objective target values during the rehabilitation process.

Inter-Limb Asymmetry in Force Accuracy and Steadiness Changes after a 12-Week Strength Training Program in Young Healthy Men

The study aimed to investigate the impact of a 12-week strength training program on force accuracy and steadiness changes in lower limbs in young healthy men. Twenty subjects with a dominant right lower limb were included. They performed a force matching task both pre and post strength training program. The ability to reproduce force was determined by calculating three errors: absolute error (AE), constant error (CE), and variable error (VE). After intervention AE and VE improved in both legs indicating higher improvement in the dominant leg (p = 0.032 for AE and p = 0.005 for VE). However, CE improved only in the dominant leg (p = 0.001). We conclude that strength training improved the accuracy and consistency of force in a force reproduction task. This improvement was more evident in the dominant lower limb. Most likely, the inter-limb asymmetry in changes of force application ability caused by strength training is due to the different mechanisms responsible for the control of voluntary movements in the dominant and non-dominant lower limb.

Effects of increasing axial load on cervical motor control

To investigate the effects of increasing axial load on cervical motor control. Surrogates of cervical motor control were active cervical range of motion (C-ROM) and joint position error (JPE) assessed in flexion, extension, lateroflexion and rotation directions in 49 healthy young men (mean age: 20.2 years). All measurements were executed with 0-, 1-, 2-, and 3-kg axial loads. Linear mixed models were used to assess the effects of axial loading and cervical movement-direction on C-ROM and JPE. Post-hoc analysis was performed to compare load levels. Axial loading (p = 0.045) and movement direction (p < 0.001) showed significant main effects on C-ROM as well as an interaction (p < 0.001). C-ROM significantly changed with 3-kg axial load by decreaseing extension (− 13.6%) and increasing lateroflexion (+ 9.9%). No significant main effect was observed of axial loading on JPE (p = 0.139). Cervical motor control is influenced by axial loading, which results in decreased C-ROM in extension and increased C-ROM lateroflexion direction.

Assessing the concurrent validity and reliability of an iPhone application for the measurement of range of motion and joint position sense in knee and ankle joints of young adults

OBJECTIVE

To analyze the concurrent validity and reliability of an iPhone application for assessing range of motion (ROM) and joint position sense (JPS) in ankle and knee joints.

DESIGN

Cross-sectional study.

SETTING

Sport laboratory.

PARTICIPANTS

Twenty healthy and physically active volunteers.

INTERVENTIONS

All participants performed a ROM and a JPS test in ankle and knee joints, which were simultaneously evaluated with photo-analysis and the iPhone application.

MAIN OUTCOMES MEASURES

A total of 80 angles were obtained with the iPhone app and the photo-analysis and compared for concurrent validity. Reliability was evaluated through re-scoring of images with the iPhone app by two different testers.

RESULTS

Very high correlation was observed between both methods for ankle and knee ROM and knee JPS (r > 0.90), and high correlation for ankle JPS (r = 0.71-0.90), while Bland-Altman plots showed absolute agreement for all the variables. Inter- and intra-tester reliability was perfect for all the variables (ICC > 0.81), except for the inter-tester reliability of ankle JPS, which was substantial (ICC = 0.61-0.81).

CONCLUSIONS

This new iPhone application is valid and reliable for measuring ankle and knee ROM and JPS, although special attention is needed during ankle evaluation to avoid errors.

Correlation of force sense error test measured by a pressure biofeedback unit and EMG activity of quadriceps femoris in healthy individuals

BACKGROUND

Our study developed a force sense error test (FSET) method for use on the quadriceps muscle, which could be employed in clinical practice to correlate the results of quadriceps muscle activity levels determined by surface electromyography (sEMG).

METHODS

Twenty-four healthy individuals were included in the study. A pressure biofeedback unit (PBU) placed under the knee joint, was used for force sense error test (FSET) evaluation. First, a maximum contraction value was determined with the PBU. Next, 50% and 65% of the maximum contraction value were used for the analysis. Concurrently, norm values for the quadriceps muscle activity levels were determined by sEMG. Simultaneously, quadriceps muscle activity levels were recorded while testing the FSET using the PBU. Each measurement was repeated in triplicate, and the average constant errors observed by the PBU were recorded in mmHg.

RESULTS

The FSET for both 50% and 65% of the normal mmHg value determined using the PBU positively correlated with activity change levels in the quadriceps muscle determined by sEMG (p < 0.05).

CONCLUSIONS

The relationship between the FSET measured using PBU and changes in the level of activity in the quadriceps muscle showed that a PBU can be used in clinical practice for proprioceptive evaluation of the knee region.