Vertical Strength Transfer Phenomenon Between Upper Body and Lower Body Exercise: Systematic Scoping Review

Area of Science:

• Exercise Physiology
• Sports Science
• Neuroscience

Background:

• Upper body (UB) and lower body (LB) exercises are common, but the impact of training one region on the other (vertical strength transfer) is not fully understood.
• Investigating how different exercise configurations influence physiological adaptations in distant body regions is crucial.

Purpose of the Study:

• To determine if vertical strength transfer occurs in response to various UB and LB exercise configurations.
• To identify the underlying mechanisms responsible for vertical strength transfer.

Main Methods:

• A systematic literature search was performed in February 2024 using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) for Scoping Reviews protocol.
• Four databases (Web of Science, MEDLINE, Scopus, CINAHL) were searched to identify relevant peer-reviewed articles.

Main Results:

• Twenty-four studies met the inclusion criteria from 5242 identified articles.
• Adding UB strength training to LB endurance exercise may preserve leg muscle power.
• Systemic endocrine responses and increased central neural drive appear to be key mechanisms driving vertical strength transfer, enhancing strength gains in untrained regions.

Conclusions:

• Vertical strength transfer is primarily mediated by neurophysiological mechanisms.
• Future research should focus on athletic populations to explore its potential for enhancing athletic performance and aiding recovery in injured extremities.