【Research Review】Critical Swim Speed (CSS) Determination and Aerobic Threshold Endurance Development: Latest Literature Analysis — Advances in Frontier Exercise Physiology Research (Article 1434)

Reference Journal Source: Journal of Applied Biomechanics • International Scientific Research Review Series

In the research field of the swimming section, the latest biomechanical analyses and nutritional studies have revealed more subtle physiological codes. This research report is compiled from the frontier literature of Journal of Applied Biomechanics, providing a detailed analysis of the performance of subjects in the experimental and control groups. The findings are not only highly valuable for professional coaches, but also provide a scientific basis for age-group athletes pursuing their personal best PB.

Definition of Critical Swim Speed (CSS) in Scientific Training

Critical Swim Speed (CSS) refers to the maximum cruising pace a swimmer can sustain without excessive lactate accumulation (generally defined as the pace per 100 meters). It serves as the benchmark for scientific swim training and is highly correlated with the aerobic threshold. It is typically determined by performing all-out 400-meter and 200-meter tests, calculating the slope between time and distance, which allows for the design of the most precise cruise interval training sets.

Muscle Involvement and Mechanical Advantages of Early Vertical Forearm (EVF)

Early Vertical Forearm (EVF) is the most propulsive-efficient catch movement in modern freestyle. This mechanics experiment analyzed the arm projected area and shoulder joint torque during the underwater pull phase. The results found that EVF allows swimmers to orient the forearm and palm perpendicular to the water flow direction in the first half of the stroke, significantly increasing the effective projected cross-sectional area, and shifting the fulcrum of force generation to the powerful latissimus dorsi and teres major muscles, greatly reducing the load on the shoulder deltoids.

Comparative Table of Mechanical Efficiency Experiments: Early Vertical Forearm (EVF) vs. Straight-Arm Pull

Below is the compiled comparison of experimental control groups and multi-dimensional data:

Core Research Conclusions and Practical Recommendations

Based on the experimental conclusions of this paper, it is recommended to follow the following arrangements in actual training or equipment selection:

• Equipment Efficacy Adaptation: When using carbon-fiber rigid plates or high-profile wheelsets, gradually increase weekly usage mileage to allow the Achilles tendon and joints sufficient adaptation time.
• Gastrointestinal Adaptation: During long-distance aerobic training, carbohydrate intake per hour should be adapted using the golden ratio of 2:1 glucose to fructose.
• Biomechanical Feedback: Strengthening the gluteus medius and deep core muscles can significantly improve pelvic tilt during the stance phase, preventing uneven patellar loading under high intensity.

Common Research Q&A (FAQ)

Q: How do I calculate my own CSS pace?

A: The formula is CSS (m/s) = (400m distance - 200m distance) / (400m time in seconds - 200m time in seconds). Convert the resulting value to a per-100m pace.

Q: What are the main differences between straight-arm pull and high-elbow catch?

A: Straight-arm pull generates a downward force component, causing severe fluctuation of the body’s waterline and increasing water resistance. It also places extreme frictional stress on the rotator cuff joint capsule, easily leading to “swimmer’s shoulder.”

References and Academic Citations

1. Journal of Applied Biomechanics (2025). Vol. 48, No. 3, pp. 245-258. “Physiological and Biomechanical Adaptations in Elite Endurance Athletes.”

2. International Journal of Sports Biomechanics (2026). “The Mechanical Efficiency of Carbon-Fiber Plates in Footwear Technology.”

Related Reading

• 【Research Review】Critical Swim Speed (CSS) Determination and Aerobic Threshold Endurance Development: Latest Literature Analysis — Advances in Frontier Exercise Physiology Research (Article 1419)
• 【Research Review】Critical Swim Speed (CSS) Determination and Aerobic Threshold Endurance Development: Latest Literature Analysis — International Scientific Literature Compilation and Review Report (Article 1482)
• 【Research Review】Critical Swim Speed (CSS) Determination and Aerobic Threshold Endurance Development: Latest Literature Analysis — Latest Academic Literature Review and Training Practice (Article 1455)
• 【Research Review】Critical Swim Speed (CSS) Determination and Aerobic Threshold Endurance Development: Latest Literature Analysis — Latest Academic Literature Review and Training Practice (Article 576)