Stage 2: Stimulus-Recovery-Adaptation

Stimulus-Recovery-Adaptation (SRA)

• SRA describes the sequence of processes during and after training
• These processes lead to improvements in size and strength
• It's a sport science concept, derived from the General Adaptation Syndrome (GAS)
• SRA is crucial for every training session and the period before the next session
• The graph below visually represents the SRA cycle

Scientific Definition of Stimulus-Recovery-Adaptation

• Stimulus: The period of time during training when exercise causes disruption to the various systems in the body.
• Recovery: The period of time after the stimulus where systems return to a normal state after being disturbed by training
• Adaptation: The process that occurs when the body's systems adjust to the stimulus and recovery, resulting in improvements in size, strength, or performance.
• It's important to consider the nature of the disruption since performance can continue to decline hours and days after the stimulus itself.
• Muscle size reduction occurs after hard workouts as immune systems and satellite cells repair damaged muscle fibers.
• Similar processes happen in the nervous system (e.g., whole-movement performance can decrease for hours and days after intense training before recovering).

System-Specific SRA Curves

• Each SRA curve represents an averaging of multiple curves generated in each session.
• Different systems in the body experience their own SRA curves at individual timescales during training.
• Powerlifting training produces 4 distinct SRA curve types with different average timescales which include: nervous system technical ability, hypertrophy, nervous system force output, and fiber alignment/connective tissue integrity curves.

Nervous System: Technical Ability Curve

• Training improves the nervous system's ability to execute movements efficiently.
• Initial session and for hours after can impact technique.
• It may take a few hours for the nervous system to recover its ability to execute those certain patterns or movements.

Muscle Hypertrophy Curve

• Muscle size is the most important factor in strength.
• Muscle catabolism (breakdown) actually increases during training and size diminishes, but increases afterwards.
• The fractional synthetic rate of muscle growth (FSR) increases, and size return occurs after an overload session.
• SRA dynamics are important for powerlifting programs

Nervous System Force Output Curve

• The nervous system coordinates muscle contraction and relaxation to produce movement patterns.
• It also has the ability to control the magnitude of that movement.
• Experience impacts the force produced
• SRA curve for nervous system output may take a week to peak

Connective Tissue Integrity Curve

• Connective tissues like tendons and ligaments are damaged during training, and their recovery takes a considerable amount of time.
• The vascularity of tendon and ligaments is lower, which causes a slower recovery rate.
• A significant drop in connective tissue integrity in training can lead to weeks or even months.
• In order to get the best results when training connective tissues, it may be appropriate to alternate intense training periods with periods of less intense training.

Relative magnitudes of SRA curves & training frequencies

• Different types of training workouts produce different effects on various body systems.
• Each type of training will likely result in larger elevations than others
• Light Sessions Technique Practice: greatest magnitude of change
• Hypertrophy Training: greatest muscle growth
• Strength Training: greatest force production
• Peaking Training: greatest connective tissue reconstruction

Principle Importance Rank

• SRA is an important concept in powerlifting for optimal training, but it's not ranked as the highest-priority principle.
• Training at any reasonable frequency can generally improve all four systems, though possibly not to the greatest extent if the training protocol is not optimized.
• Both benefits and costs exist with improper structure of SRA curves and frequencies(a smaller negative versus violations of overload, and fatigue management)

Optimal Frequencies of Training

• The definition of SRA implies that several systems in the body experience their own unique timescales for adapting to training stimuli and recovering and then are ready to be loaded again.
  • This concept is crucial for creating a training program that optimizes the growth and development of each system.

Training that is Too Clustered

• Overloading training sessions too soon after the previous session or very close to the next can interfere with performance and recovery.
• This is mainly due to an accumulation of fatigue from previous sessions

Training that is Too Low in Frequency

• If training is not frequent enough, the lifter might not reach all of their training goals.
• For specific systems, high frequencies are often necessary to optimize gains.
• An extreme lack of frequency and overtraining in the body is equally bad. It has a big negative effect on the adaptive magnitude of training.

Arrangement of Training Days

• The schedule or order of training sessions makes a difference in training's effectiveness.
• For example, training the lower body three times a week can be achieved in many different ways (Monday, Wednesday, Friday, or other days)

This quiz explores the concept of Stimulus-Recovery-Adaptation (SRA) in sports science. It covers the processes involved during and after training that lead to improvements in strength and performance. Understanding SRA is essential for optimizing training sessions and recovery periods.