Glödljus och kall LED-belysning är förknippade med skilda fysiologiska och perceptuella responser under återhämtning efter isometriskt handgrepp
Year: 2026
Type: dissertation
Abstract: This study examined whether two common indoor lighting conditions were associated with different physiological and perceptual responses during three task phases: baseline, isometric handgrip (IHG), and recovery. In a randomized within-subject crossover protocol, 17 participants completed both an incandescent condition (2700 K) and a cool LED condition (6500 K), matched at 210 lux (± 5). The primary physiological outcome was PPG-derived RMSSD, a measure of heart rate variability (HRV). Complementary outcomes included two additional HRV indices, lnRMSSD and pNN50, and heart rate (HR). Perceptual outcomes were affective valence, activation/arousal, perceived exertion, and prospective time perception. The main analysis showed a significant main effect of light on RMSSD (p = .037, ηp² = .24) and a significant main effect of phase (p = .008, ηp² = .26), but no Light × Phase interaction. Planned recovery comparisons showed significantly higher RMSSD and lnRMSSD under incandescent light than under cool LED light with Bonferroni correction; higher pNN50 was observed (p = .018, ηp² = .054) and recovery HR did not differ significantly. Affective valence, activation, and time perception all changed across phase, although there was not a main effect of Light or a Light × Phase interaction. Perceived exertion was significantly higher during IHG, but did not differ between light conditions. The overall pattern of responses indicated a physiological-perceptual dissociation; lighting was associated with differences in PPG-derived HRV indices during recovery, but these differences were not associated with perceptual measures. It warrants acknowledging that the findings of the present study should be interpreted cautiously due to the small sample size, the acute light exposure, and measure of HRV derived from PPG rather than ECG. Preliminary findings suggest that further study of the influence of common indoor lighting conditions on psychophysiological aspects of short-term recovery is justified.
Authors: Pålsson, Jonatan, Andersson, Carl-Philip
Language: English
Subfield: Cardiology and Cardiovascular Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W7166270163