An investigation into the effect of unilateral immobilisation of the upper limb on the physiological responses to stair climbing

Introduction: Musculoskeletal conditions or injuries to the shoulder are frequently seen within primary healthcare practice, with a number of these complaints resulting in restricted joint mobility. It is known that minor restrictions to movement, particularly those that disrupt the normal gait cycle, result in an increased energy demand. Though previous studies have not demonstrated any increase in energy demand during a level walking task with an immobilised upper limb, the extent to which upper limb immobilisation during stair climbing has on physiological outcomes has yet to be determined. Purpose: The objective of this study was to measure the effect of unilateral restriction of upper limb on energetic cost of stair climbing. Methods: Thirty four participants, 16 males (age 28 ± 9 years, height 181 ± 6cm, weight 75 ± 13kg) and 18 females (age 23 ± 4 years, height 170 ± 5cm, weight 64 ± 6kg) ascended a public access staircase at a rate of 80 steps.min-1 for five minutes and fifteen seconds over two experimental trials. Participants were randomly assigned to conduct the trial with complete mobility, followed by immobilisation of the dominant (n=17) or non-dominant (n=17) upper extremity, or vice versa. Outcome measures of oxygen uptake (mL.kg-1.min-1), total energy cost (kcal.d-1), relative energy expenditure (kcal.d-1.kg-1) and heart rate (beats.min-1) were recorded and utilised in data analysis, relating to pre- (0 minutes 0 seconds) versus post- (5 minutes 15 seconds) the experimental time both within and between the groups (immobilised and non-immobilised). Results: Post stair climb data shows only a trivial to small difference in the physiological measures of the non-immobilised and immobilised groups (oxygen uptake; 1.4 ± 0.5 and 1.4 ± 0.4mL.min-1.kg-1, heart rate; 58 ± 16 and 59 ± 16beats.min-1, total energy cost; 9858 ± 3560 and 10499 ± 3062kcal.d-1, and relative energy expenditure 139 ± 42 and 149 ± 39kcal.d-1.kg-1, respectively). A trivial to small difference in the physiological measures in the two groups prior to the stair climb task (oxygen uptake; 0.5 ± 0.2 and 0.5 ± 0.2mL.min-1.kg-1, heart rate; 103 ± 19 and 106 ± 14beats.min-1, total energy cost; 3711 ± 1555 and 3362 ± 1419kcal.d-1, and relative energy expenditure 53 ± 23 and 48 ± 21kcal.d-1.kg-1, , respectively) and a large difference pre- to post- the stair climbing task in the outcome measures was observed. Additional analysis demonstrates only a trivial to small difference in the physiological measures between order of immobilisation, and between immobilisation of the dominant or non-dominant upper limb. Conclusion: Immobilisation of the upper limb had only a trivial to small effect on oxygen uptake, heart rate, total energy cost, and relative energy expenditure during a stair climbing task