Effects of exercise on the immune system in pediatric acute lymphoblastic leukemia (ALL) patients.

Leukemia accounts for 30% of cancer in children 0 to 14 years and 25% of
cancers occurring before age 20. Acute lymphoblastic leukemia (ALL) is the most
common childhood cancer. Chemotherapy treatments for ALL cause
immunosuppression, leading to an increase in susceptibility to infections,
requiring reconstitution of immune function after treatment. Literature
pertaining to the relationship between risk of infection and physical activity
is sparse, but for the general population of healthy active children, increased
levels of physical activity are associated with reduced susceptibility to
respiratory infections. In contrast, the available evidence in adults suggests
that high volume sport training can increase the susceptibility to illness and
infection.
Exercise scientists have been investigating, for some time, how acute and
chronic exercise might influence the immune system*s ability to combat
infection and illness. Despite the proliferation of this field, however, there
remains a paucity of studies devoted to the pediatric population. Consequently,
very little is known regarding the interactions of acute and chronic exercise
and the immune system in children and adolescents and their implications for
health and disease.
There is substantial evidence to show that physical exercise can produce
desirable changes in the distribution and function of cellular and humoral
components of the immune system in healthy children and adolescents. Moreover,
current research shows that physical training becomes more important in the
rehabilitation of children and adults with cancer and survivors. More evidence
on the acute and chronic effects of exercise in this population is needed to
establish the safety of exercise and its optimum to rule out adverse effects of
exercise on the compromised immune system of children with cancer.
In short, therapeutic advances have created an increasing number of childhood
survivors of cancer. For these children, physical activity is beneficial, but
only if the *exercise dose* does not exacerbate the inflammatory status
abnormalities. Identifying *optimal* levels and safe limits of exercise
training must be based on a better understanding of the mechanisms that link
exercise as a therapeutic tool with the health benefits in the growing child
with cancer.

What is the effect of different bouts of exercise on the immune system in
patients with acute lymphoblastic leukemia?

This study is a intervention study in children with ALL.

Three different bouts of exercise: cycle ergometer test, active computer game
and physical therapy session

Participants will be asked to perform a graded maximal exercise test to measure
VO2peak (session 1) and to take part in three exercise sessions (session 2-4)
that will last approximately 1 hour. They will be asked to fill out a physical
exercise enjoyment scale after each session and a habitual physical exercise
questionnaire once. To measure the habitual physical exercise objectively, the
children wil carry an accelerometer (Actical) attached to their belt during a
week

The level of discomfort should be minimal as all of these sessions are safe for
children to perform. They may experience some muscle soreness or stiffness, but
this should not worsen their disease or disability. During the three exercise
sessions blood samples will be collected at 3 time points: pre-exercise,
post-exercise, and 1-hour post-exercise. In total 9 blood samples will be taken
from each participant, in which only three times we need to insert an entry to
draw blood. Most of the children with ALL do have a port-a-cath (PAC). All the
collections will be performed by M Kruijsen-Jaarsma, MD. Anthropometric
measurements consist of weight, length and three skin fold measurements. The
risks and side-effects of the exercise will be minimal. Moreover, the physical
exercise has also a lot of benefits: exercise can improve aerobic fitness and
improve health related quality of life. Drawing blood is an intervention that
will not be seen as minimal.