Effect of Exercise Performed during Hemodialysis: Strength versus Aerobic

Figures & data

Figure 1. Flowchart, process of randomization (Consort 2010). Note: *TCLE = Informed Consent Form.

Table 1. Sample characteristics.

Characteristics	Control group (G1)	Strength group (G2)	Aerobic group (G3)
	(n = 11)	(n = 11)	(n = 10)
Gender, n
Male	6	7	5
Female	5	4	5
Age (years)	43.5 ± 11.1	49.6 ± 9.1	43.1 ± 13.3
Weight (kg)	68.4 ± 12.2	73.6 ± 14.6	58.9 ± 9
Height (m)	1.70 ± 0.1	1.70 ± 0.1	1.64 ± 0.1
BMI (kg/m^2)	27.4 ± 3.7	26.0 ± 5.1	22.99 ± 5.6
Comorbidities
Hypertension	8	8	6
CCF		3	1
Diabetes	1	2	2
Smoking habits
Never smoked	10	7	8
Former smoker	0	1	1
Smoker	1	3	1
Hemodialysis time (years)	6.5 ± 4,2	5.4 ± 4	6.4 ± 4.4
MIP (cmH2O)	59.1 ± 18	60.1 ± 23	59.5 ± 29.3
MEP (cmH2O)	59 ± 15	62 ± 21	70 ± 27
FEV1 (L)	2.4 ± 0.6	2.4 ± 0.6	2.1 ± 0.4
FVC (L)	2.7 ± 0.7	2.5 ± 0.5	2.5 ± 0.8
FEV1/FVC (L)	0.92 ± 0.11	0.9 ± 0.1	0.91 ± 0.07

Note: BMI, body mass index; CCF, congestive cardiac failure; MIP, maximal inspiratory pressure; MEP, maximal expiratory pressure; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; FEV₁/FVC, Tiffeneau index

Table 2. Intragroup analysis: respiratory muscles strength, pulmonary function, and tolerance to submaximal exercise.

Variables	Predicted	Control group (G1)			Strength group (G2)			Aerobic group (G3)
		Pre-	Post-	p-Value	Pre-	Post-	p-Value	Pre-	Post-	p-Value
MIP (cmH2O)	−104 ± 16	−59.1 ± 18	−52.7 ± 14	0.363	−60.1 ± 23	−93.5 ± 21**	0.0022	−59.5 ± 29.3	−92.3 ± 22.1	0.0112
MEP (cmH2O)	108 ± 25	59 ± 15	60.5 ± 17	0.82	62 ± 21	101 ± 18**	0.0002	70 ± 27	97 ± 31	0.052
FEV1	3.2 ± 0.6	2.4 ± 0.6	2.3 ± 0.6	0.713	2.4 ± 0.6	2.7 ± 0.5	0.21	2.1 ± 0.4	2.7 ± 0.9	0.7
FVC (L)	3.9 ± 0.8	2.7 ± 0.7	2.5 ± 0.7	0.51	2.5 ± 0.5	3 ± 0.7	0.068	2.5 ± 0.8	3.1 ± 1	0.155
FEV1/FVC (L)	0.8 ± 0.0	0.92 ± 0.11	0.85 ± 0.14	0.207	0.9 ± 0.1	0.9 ± 0.11	0.999	0.91 ± 0.07	0.9 ± 0.07	0.753
NSA (6 min)	ND	101 ± 23	92.5 ± 21	0.1899	69 ± 25	131 ± 31**	0.0001**	86 ± 36	142 ± 32**	0.0018**

Notes: Data presented as average ± standard deviation. ANOVA utilized, followed by post-hoc Student Newmann-Keuls. MIP, maximal inspiratory pressure; MEP, maximal expiratory pressure; FEV₁, forced expiratory volume in 1 s; FVC, forced vital capacity; FEV₁/FVC, Tiffeneau index; NSA, number of steps achieved; ND, not defined.

*p < 0.05; **p < 0.001.

Table 3. Blood biochemistry.

Electrolytes	G1 (Strength)		G2 (Aerobic)		G3 (Control)
	Pre	Post	Pre	Post	Pre	Post
Urea (mg/dL)	184 ± 44	178 ± 38	169 ± 42	135 ± 27	167 ± 30	163 ± 29
Potassium (mEq/L)	6.1 ± 0.7	5.6 ± 0.7	5.5 ± 0.6	5.3 ± 0.7	6.2 ± 0.7	5.8 ± 0.6
Phosphorus (mg/dL)	6.2 ± 1.3	6.6 ± 1.6	5.6 ± 1.8	5.4 ± 1.7	5.4 ± 1.3	5.6 ± 0.9
Calcium (mg/dL)	9.3 ± 0.9	10.1 ± 2.6	9 ± 1.5	8.6 ± 1.3	9.4 ± 0.5	9.3 ± 0.9
Hematocrit (%)	35.6 ± 2.8	35.9 ± 2.5	34.9 ± 3	32.1 ± 3.2	35.4 ± 1.5	34.5 ± 3
Hemoglobin (g/dL)	11.3 ± 1	11.4 ± 0.9	11.3 ± 0.9	10.3 ± 0.9	11.1 ± 0.7	11.1 ± 1.2

Notes: We utilized ANOVA with post-hoc Student–Newman–Keul.*In the comparison of aerobic versus strength groups, p < 0.05. When comparing the aerobic group pre- versus post-exercise condition, p = 0.032.