HIIT-the track: High Intensity Interval cycle-ergometer exercise Training in people with Parkinson*s Disease

People with Parkinson's disease (PD) experience not only motor problems (e.g.
with posture, walking and balance) but also non-motor problems (e.g. with
regard to cognition, mood, biorhythm, fatigue etc.) that seriously hinder their
daily functioning. Current pharmacological treatments are insufficient to
adequately improve these problems. Therefore, alternative rehabilitation
treatments are needed, which preferably also have a disease-modifying effect on
both motor and non-motor symptoms and promote neuroplasticity.
Intensive physical training appears to be very promising for promoting
neuroplasticity in people with PD. In particular biomarkers for neuroplasticity
such as Brain-derived neurotrophic factor (BDNF, decrease) and
neurodegeneration (including neurofilament NfL, increase) are abnormal in
people with PD. BDNF has shown to respond well to intensive physical training,
for NfL this has not yet been properly investigated. With highly intensive
physical training, walking, balance, cognition and mood can improve. However,
the optimal type of physical training to achieve these neuroplastic effects is
unknown. High Intensity Interval Training (HIIT) appears to be a superior
training strategy over traditional moderate "continuous aerobic exercise" (CAE)
in terms of physical and neurotrophic effects, with significantly less total
training time and burden. Although promising, this training strategy has not
yet been well studied in people with PD.

1) to study the effects of 4 weeks of HIIT compared to 4 weeks of CAE on motor
and non-motor aspects of PD; 2) to investigate the association between blood
biomarkers for neuroplasticity / neurodegeneration and motor and non-motor
performance for both exercise strategies.

Single Subject Research Design (SSRD) with alternating treatment setup (ABACA)
and frequent repeated measurements. Here a single participant receives
different interventions (B / C) interspersed with baseline periods (A, i.e.
ABACA or ACABA) and frequent repeated measurements are done over time to
quantify the within-subject, individual response patterns with sufficient power
for data analysis.
Data analysis: Individual recovery curves are analyzed with visual inspection
of between and within phase change, spread and trend. In addition, Pearson
correlation coefficients will be calculated for the relationship between motor
and non-motor outcomes and neuroplasticity / neurodegeneration markers. We
expect that HIIT as compared to CAE will be superior in inducing
neuroplasticity related, disease modifying effects.

Participants will perform alternate (scheme will be ABACA or ACABA) schedules
of 30 minute sessions of B (HIIT) or 50 minute sessions of C (CAE 3x / week for
4 weeks) separated by baseline (A) periods of 8 weeks for a total duration of
28 weeks.

All participants will receive, and may benefit from, the training interventions
as all participants receive both types of interventions. They will need to come
to the VUmc outpatient clinic for training 3x/week during the 4 week
intervention periods. Assessment time will be combined with training times as
much as possible. During A phases, on multiple time points, extra time will be
asked of the patients for home based short answer questions on a smartphone and
outpatient visits to assess other outcome parameters.