CSC Speed and Agility Training 1 — Questions and Answers
Question 1: Which phase of sprinting requires the greatest lower-body strength relative to body weight?
- Top-speed maintenance phase
- Deceleration phase
- Acceleration phase (Correct answer)
- Upright running phase
Correct answer: Acceleration phase
The acceleration phase demands the highest ground reaction forces relative to body weight as athletes push horizontally from a low body angle against the ground.
Question 2: What is the definition of reactive strength index (RSI)?
- Peak force divided by body mass during a squat jump
- Jump height divided by ground contact time during drop jumps (Correct answer)
- Rate of force development during a countermovement jump
- Maximal power output during repeated sprints
Correct answer: Jump height divided by ground contact time during drop jumps
RSI is calculated by dividing jump height by ground contact time, providing a measure of the ability to rapidly absorb and redirect force in stretch-shortening cycle activities.
Question 3: Which of the following best describes the stretch-shortening cycle (SSC) and its role in speed development?
- A passive lengthening of muscle with no energy storage
- A rapid eccentric-to-concentric contraction that stores and releases elastic energy (Correct answer)
- A concentric-only muscle action during jumping
- The slow loading of tendons before a lift
Correct answer: A rapid eccentric-to-concentric contraction that stores and releases elastic energy
The SSC involves a rapid eccentric (pre-loading) phase followed immediately by a concentric phase, allowing elastic energy stored in tendons to enhance force output beyond what muscle alone produces.
Question 4: What is the most effective training method for improving an athlete's first-step quickness?
- Long slow distance runs
- Heavy back squats only
- Resisted sprint starts and reaction drills (Correct answer)
- High-volume low-intensity plyometrics
Correct answer: Resisted sprint starts and reaction drills
Resisted sprint starts (with sleds or bands) develop horizontal force production, and reaction drills train the neural component of first-step quickness.
Question 5: Which mechanical variable is most strongly correlated with maximum sprint velocity in elite sprinters?
- Step frequency (cadence)
- Hip flexor flexibility
- Vertical ground reaction force during stance (Correct answer)
- Trunk forward lean angle
Correct answer: Vertical ground reaction force during stance
Research consistently shows that the magnitude of vertical ground reaction force applied during the brief stance phase is the primary determinant of maximum sprint velocity.
Question 6: What is the primary purpose of a deceleration training program for team sport athletes?
- To improve maximum sprint speed
- To increase stride length
- To reduce ACL injury risk during high-speed changes of direction (Correct answer)
- To develop aerobic capacity
Correct answer: To reduce ACL injury risk during high-speed changes of direction
Deceleration training teaches athletes to safely absorb and control high ground reaction forces during stopping and direction changes, significantly reducing ACL and lower-extremity injury risk.
Which phase of sprinting requires the greatest lower-body strength relative to body weight?