Table 4. Mean differences between the CF and healthy groups for lung function variables at rest and cardio-respiratory variables while walking, for the three backpack positions.

	Mean differences between change in backpack carrying positions in the healthy and CF groups
	From NB to BB 95% CI	p-value	From NB to UB 95%CI	p-value	From BB to UB 95%CI	p-value
FVC L	0.02 [-0.12 to 0.16]	NS	-0.03 [-0.13 to 0.07]	NS	-0.02 [-0.17 to 0.14]	NS
FVC %	0.25 [-4 to 4.5]	NS	-0.44 [-3.28 to 2.4]	NS	-0.21 [-4.55 to 4.13]	NS
FEV1 L	0.01 [-0.09 to 0.12]	NS	-0.12 [-0.18 to -0.05]	0.025	-0.10 [-0.19 to -0.01]	0.030
FEV1%	-0.02 [-3.53 to 3.48]	NS	-4.10 [-6.46 to -1.75]	0.019	-4.12 [-7.45 to -0.80]	0.024
PEF L/min	-0.04 [-0.52 to 0.43]	NS	0.01 [-0.49 to 0.51]	NS	-0.03 [-0.55 to 0.48]	NS
MIP cmH2O	-3.32 [-15.73 to 9.09]	NS	-6.86 [-21.86 to 8.14]	NS	-10.63 [-22.2 to -0.91]	0.041
MEP cmH2O	-3.83 [-20.87 to 13.2]	NS	-5.65 [-17.76 to 6.45]	NS	-9.49 [-23.2 to 4.05]	NS
MV L/min	0.80 [-0.2 to 1.80]	NS	1.05 [-0.45 to 2.55]	NS	1.85 [0.3 to 3.39]	0.029
Dyspnea Borg	0.01 [-0.80 to 0.81]	NS	0.53 [-0.42 to 1.47]	NS	0.54 [-0.81 to 1.88]	NS
RR cpm	1.26 [0.10 to 2.62]	0.034	1.51 [0.16 to 2.86]	0.02	2.77 [0.7 to 4.84]]	0.024
VO2 mL/min	22.2 [7.7 to 36.7]	0.045	54.5 [32 to 77]	0.027	17 [-3.8 to 37.9]	NS
VCO2 mL/min	13.3 [-0.8 to 27.5]	NS	16.9 [-3.7 to 37.5]	NS	8 [-11 to 27]	NS

Abbreviations: BB: bilateral backpack carrying; FEV1: forced expiratory volume in 1 second; FVC: forced vital capacity; MEP: maximal expiratory pressure; MIP: maximal inspiratory pressure; MV: minute ventilation; NB: no backpack carrying; PEF: peak expiratory flow; RR: respiratory rate; UB: unilateral backpack carrying; VCO2: carbon dioxide production; VO2: oxygen consumption. Values are expressed as mean differences between backpack carrying positions in CF and healthy groups and are expressed as Means [95% CI]; p-values are indicated for post-hoc analyses comparing between-groups differences between backpack positions in both groups