title: Neuromuscular and cardiovascular responses of Royal Marine recruits to load carriage in the field.
abstract: Cardiovascular and neuromuscular responses of 12 male Royal Marine recruits (age 22 ± 3 years, body mass 80.7 ± 6.8 kg, VO(2)max 52.3 ± 2.7 ml kg(-1) min(-1)) were measured during 19.3 km of load carriage walking at 4.2 km h(-1) and carrying 31.0 kg. Heart rate during load carriage was 145 ± 10 beats·min(-1) (64 ± 5 %HRR) and showed a negative relationship with body mass (r = -0.72, P = 0.009) but no relationship with VO(2)max (ml kg(-1) min(-1); r = -0.40, P = 0.198). Load carriage caused a decrease in vertical jump height (8 ± 9%) and power (5 ± 5%) (P < 0.001). Change in vertical jump power showed a positive relationship with body mass (r(2) = 0.40, P = 0.029) but no relationship to VO(2)max (ml kg(-1) min(-1); r(2) = 0.13, P = 0.257). In conclusion, load carriage caused a reduction in vertical jump performance (i.e. decreased neuromuscular function). Lighter individuals were disadvantaged when carrying absolute loads, as they experienced higher cardiovascular strain and greater decreases in neuromuscular function.
authors.affiliation: Institute of Naval Medicine, Gosport, Hampshire, UK. Joanne.Fallowfield258@mod.uk
authors.forename: Joanne L
authors.initials: JL
authors.lastname: Fallowfield
authors.forename: Sam D
authors.initials: SD
authors.lastname: Blacker
authors.forename: Mark E T
authors.initials: ME
authors.lastname: Willems
authors.forename: Trish
authors.initials: T
authors.lastname: Davey
authors.forename: Joseph
authors.initials: J
authors.lastname: Layden
mesh_terms: D000328:Adult; D001835:Body Weight; D006339:Heart Rate; D006801:Humans; D017770:Lifting; D008297:Male; D008889:Military Personnel; D009068:Movement; D018763:Muscle Fatigue; D053580:Muscle Strength; D018482:Muscle, Skeletal / Q000502:physiology; D010101:Oxygen Consumption; D005082:Physical Exertion / Q000502:physiology*; D018709:Statistics, Nonparametric; D013647:Task Performance and Analysis; D006113:United Kingdom; D016138:Walking / Q000502:physiology*; D055815:Young Adult