Instruction during lifting: How analogy and explicit instruction influence performance and motor control

Area of Science:

• Motor Learning and Control
• Biomechanics and Exercise Physiology

Background:

• Traditional weightlifting coaching often uses explicit verbal cues.
• Emerging research suggests analogy-based instructions may enhance motor learning through implicit control.

Purpose of the Study:

• To investigate the impact of analogy (ANA) and explicit (EXP) verbal instructions on motor performance and muscle activation during weightlifting.
• To compare the effectiveness of different instructional strategies on neuromuscular control and force production in novice lifters.

Main Methods:

• Twenty novice participants were randomly assigned to ANA, EXP, or control groups.
• A within-participant design counterbalanced conditions over three days, including familiarization, control, and experimental conditions.
• Muscle activity (EMG), force production, and declarative knowledge were assessed during isometric and dynamic lifting tasks.

Main Results:

• Both ANA and EXP instructions led to significant changes in lower limb EMG activity, indicating motor control reorganization.
• The EXP group showed significantly reduced rate of force development in the initial 200 ms compared to the control group.
• The control group exhibited higher overall force output, suggesting verbal instruction may impede maximal force production.

Conclusions:

• Avoiding verbal instruction may be beneficial for maximizing force output in weightlifting.
• Analogy instructions appear to preserve performance levels while modifying neuromuscular strategies.
• Verbal instructions, particularly explicit ones, may alter motor control in ways that reduce initial force development.