The Combination of Plantar Pressure Plate and Foot Muscle Fatigue Detection is a Multimodal Biomechanical Analysis Method
By synchronously acquiring plantar pressure distribution data and muscle electrical activity signals, it enables a comprehensive assessment of foot functional status.
This integrated technology can reveal the correlation mechanism between gait abnormalities and muscle fatigue, providing scientific evidence for clinical diagnosis, sports training, and rehabilitation treatment.
Core Components and Technical Solutions
1. Data Acquisition System
The plantar pressure plate adopts high-density capacitive or piezoresistive sensor arrays, capable of measuring pressure distribution in the range of 0–100 N/cm², with a sampling frequency usually between 100–200 Hz.
Modern systems support static and dynamic testing modes, able to capture plantar force characteristics during standing, walking, running, and other states.
The electromyography (EMG) system acquires electrical signals of foot muscles (such as the gastrocnemius, tibialis anterior, etc.) through surface electrodes. The sampling frequency needs to reach above 2000 Hz, combined with 20–500 Hz band-pass filtering to ensure signal quality. Advanced systems such as Trigno/Bagnoli can synchronously acquire multiple sensor signals including acceleration and magnetometer.
2. Synchronous Acquisition Technology
Key technologies to achieve data synchronization include:
- Hardware-level synchronization: Triggering data acquisition of both types of devices through a unified clock signal
- Software-level synchronization: Using timestamp alignment algorithms, with error controlled within ±5 ms
- Multimodal data fusion platforms: For example, the DELSYS system can integrate signals such as pressure, EMG, ECG, etc.
3. Data Analysis Methods
- Static analysis includes:
- Foot shape judgment and center of gravity distribution evaluation
- Calculation of unilateral plantar peak and mean pressure
- Identification of abnormal pressure distribution areas
- Dynamic analysis indicators cover:
- Gait cycle decomposition (landing, support, push-off phases)
- Center of Pressure (CoP) trajectory deviation analysis
- Spatiotemporal parameters such as step speed, step length, and step width
- Muscle fatigue assessment mainly through:
- Decline amplitude of EMG median frequency (MDF)
- Changes in muscle activation sequence
- Symmetry analysis of left and right sides
Typical Application Scenarios
1. Clinical Diagnosis and Rehabilitation
- Diabetic foot risk assessment: Combining identification of high-pressure plantar regions with muscle perfusion parameters (f-value) to predict ulcer risk
- Chronic ankle instability assessment: Analyzing the correlation between abnormal medial-lateral deviation of CoP trajectory and gastrocnemius fatigue
- Post-meniscus surgery rehabilitation: Monitoring recovery of plantar pressure distribution and quadriceps activation patterns during anti-gravity training
2. Applications in Sports Science
- Running technique optimization: Identifying the correlation between foot arch collapse after 10 km running and calf muscle fatigue, guiding footwear design
- Fatigue mechanism research: Discovering that lower limb muscle fatigue in the elderly leads to CoP trajectory approaching the midline, with movement speed reduced by 13%
- Sports injury prevention: Providing early warning of stress fracture risk by analyzing the association between abnormal metatarsal region pressure and early tibialis anterior fatigue
