Orthostatic tolerance and training methodology in physically active men and women

Area of Science:

• Exercise Physiology
• Cardiovascular Health
• Sports Science

Background:

• Previous research indicates training methodology impacts orthostatic tolerance in elite athletes.
• Limited data exists on how training affects orthostatic tolerance in the general physically active population.

Purpose of the Study:

• To investigate if hybrid training (resistance and endurance) improves orthostatic tolerance compared to endurance-only or recreational activity.
• To test the hypothesis that hybrid training enhances orthostatic tolerance in physically active adults.

Main Methods:

• Twenty-nine participants were divided into Recreationally Active, Hybrid Training, or Endurance Training groups.
• Orthostatic tolerance was assessed using a progressive lower-body negative pressure (LBNP) test, quantified by cumulative stress index (CSI).
• Body composition was measured using air displacement plethysmography.

Main Results:

• No significant difference in CSI was found between the training groups.
• Fat-free mass (FFM) was positively correlated with CSI (R² = 0.4092).
• FFM varied significantly between groups, but CSI normalized to FFM did not differ.

Conclusions:

• Training methodology does not appear to influence orthostatic tolerance in recreationally active adults.
• Body composition, particularly fat-free mass, is a key factor related to orthostatic tolerance.
• Maintaining lean mass is important for orthostatic tolerance, irrespective of specific training regimens.