A structured exercise programme during haemodialysis for patients with chronic kidney disease: clinical benefit and long-term adherence

Abstract

Objective: Long-term studies regarding the effect of a structured physical exercise programme (SPEP) during haemodialysis (HD) assessing compliance and clinical benefit are scarce.

Study design: A single-centre clinical trial, non-randomised, investigating 46 patients with HD (63.2 ± 16.3 years, male/female 24/22, dialysis vintage 4.4 years) performing an SPEP over 5 years. The SPEP (twice/week for 60 min during haemodialysis) consisted of a combined resistance (8 muscle groups) and endurance (supine bicycle ergometry) training. Exercise intensity was continuously adjusted to improvements of performance testing. Changes in endurance and resistance capacity, physical functioning and quality of life (QoL) were analysed over 1 year in addition to long-term adherence and economics of the programme over 5 years. Average power per training session, maximal strength tests (maximal exercise repetitions/min), three performance-based tests for physical function, SF36 for QoL were assessed in the beginning and every 6 months thereafter.

Results: 78% of the patients completed the programme after 1 year and 43% after 5 years. Participants were divided--according to adherence to the programme--into three groups: (1) high adherence group (HA, >80% of 104 training sessions within 12 months), (2) moderate adherence (MA, 60-80%), and 3. Low adherence group (LA, <60%)) with HA and MA evaluated quantitatively. One-year follow-up data revealed significant (p<0.05) improvement for both groups in all measured parameters: exercise capacity (HA: 55%, MA: 45%), strength (HA: >120%, MA: 40-50%), QoL in three scores of SF36 subscales and physical function in the three tests taken between 11% and 31%. Moreover, a quantitative correlation analysis revealed a close association (r=0.8) between large improvement of endurance capacity and weak physical condition (HA).

Conclusions: The exercise programme described improves physical function significantly and can be integrated into a HD routine with a high long-term adherence.

Keywords: Dialysis < NEPHROLOGY; SPORTS MEDICINE.

Figure 1

Scheme for our individual structured training to improve endurance and strength in patients with dialysis including a feedback loop. (A) The eight exercises refer to the muscle groups biceps, triceps, abductor, adductor, abdomen, back, leg extensor and leg curl. Theraband resistance and weights were increased in relation to the patient's training success; for details, see text. (B) The training was performed with letto2 Reck MOTOmed cycle ergometers which record automatically the exercise data; see text.

Figure 2

Endurance built through training on the cycle ergometer according to the scheme of figure 1. The power P_N achieved on average in month N is shown normalised to the power P₁ in month N=1. Data are taken from groups HA (>80% training participation) and MA (60–80% training participation) for parts (A) and (B), respectively. The standard error is given for each data point as well as the significance p(ANOVA) of P_N/P₁ being different from the initial value 1 at N=1 with the scale on the right side. After month 3, roughly the maximum average increase is reached (55% and 45% in groups HA and MA, respectively). This corresponds to an average power of <P₃>=22.1±2.0 W in group HA (<P₃>=19.4±3.2 W in group MA) increased from an initial average power of <P₁>=17.5±1.8 W and <P₁>=16.0±3.0 W in groups HA and MA, respectively. ANOVA, analysis of variance; HA, high adherence; MA moderate adherence.

Figure 3

The relative rate of change in power Y(P)=P^−1⋅dP/dt in two successive months as a function of the power P itself. Shown are the data of four patients (group HA, >80% training participation) with a mean power of <P> <15 W and four patients (group HA) with <P> >25 W with individual linear regression fits. HA, high adherence.

Figure 4

Correlation of the relative power improvement per work done, α (MJ⁻¹), work measured in Megajoule (determined from the negative slopes of the linear regression fits as in figure 3), and the mean power <P> for each patient from group HA. HA, high adherence.