Premium
Cold fluid ingestion extends exercise capacity of heat‐sensitive individuals with Multiple Sclerosis in a warm environment
Author(s) -
Chaseling Georgia K,
Filingeri Davide,
Hoang Phu,
Barnett Michael,
Davis Scott L,
Jay Ollie
Publication year - 2016
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.30.1_supplement.1243.13
Subject(s) - multiple sclerosis , ingestion , medicine , physical therapy , immunology
Exposure to a hot environment or heat gained during exercise can elicit a transient worsening of clinical symptoms in person with multiple sclerosis (MS), a demyelinating disease of the central nervous system). Heat‐related fatigue has been reported in 60–80% of individuals with MS, potentially limiting physical activity. Therefore, simple interventions that mitigate heat‐related reductions in exercise capacity in persons with MS are needed. Our aim was to test the hypothesis that cold fluid ingestion prolongs exercise duration of individuals with relapsing‐remitting MS cycling in a warm (30°C, 35% RH) environment. On two randomized occasions, 7 participants (54 ± 7 y; 76.1 ± 10.9 kg; 1.71 ± 0.09 m) diagnosed with relapsing‐remitting MS exercised at a low intensity (heat production: 3.2 ± 0.5 W·kg −1 ) for a maximum of 60 min (or until exhaustion), while ingesting a 3.2 mL·kg −1 aliquot every 15 min of either cold (1.5°C: CLD) or thermoneutral (37°C: NEU) water. Rectal (T re ) and mean skin (T sk ) temperature was continuously measured. Exercise duration was significantly longer (P=0.05) in the CLD trial (54.3 ± 11.0 min) compared to the NEU trial (46.4 ± 14.1 min). Indeed, after 45‐min of exercise, 3 of 7 participants remained in NEU, whereas 6 of 7 participants remained in CLD. All subjects were able to complete a minimum of 31 minutes of exercise. At this time point, absolute T re (CLD: 37.08 ± 0.34°C, NEU: 36.99 ± 0.26°C; P = 0.59), the change in T re (CLD: 0.25 ± 0.30°C, NEU: 0.25 ± 0.15°C; P =0.99), absolute T sk (CLD: 34.41 ± 0.45°C, NEU: 34.31 ± 0.30°C; P = 0.57), and the change in T sk (CLD: 1.35 ± 0.54°C, NEU: 1.41 ± 0.53°C; P = 0.63) were all similar between CLD and NEU. Additionally, at the termination end‐point of exercise, absolute T re (CLD: 37.23 ± 0.30°C, NEU: 37.20 ± 0.26°C; P = 0.82), the change in T re (CLD: 0.32 ± 0.30°C, NEU: 0.45 ± 0.18°C; P =0.70), absolute T sk (CLD: 34.81 ± 0.27°C, NEU: 34.61 ± 0.35°C; P = 0.15), and the change in T sk (CLD: 1.75 ± 0.85°C, NEU: 1.68 ± 0.88°C; P = 0.72) were all similar between CLD and NEU. In conclusion, during physical activity in a warm environment, heat‐sensitive individuals with MS exercised for longer before exhaustion with the ingestion of a cold compared to a thermoneutral fluid. Support or Funding Information This study was supported by a MS Research Australia Incubator Grant (Holders: Jay, Barnett, Hoang and Davis) and a University of Sydney International Collaboration Research Award (IRCA) (Holders: Davis and Jay). Dr Filingeri was supported by a Government of Australia Endeavour Fellowship