Ellemberg by Welk (2010). Based on previous study

Ellemberg and St- Louise-Deschenes,
2010, found that children who were given cognitive tests immediately after 30
minutes of aerobic physical activity outperformed children who watched
television for the same amount of time. This may be because physical activity
enhances memory and attention, as well as reduces anxiety, which all have been
shown to impact test performance (Ellemberg and St-Louis-Deschênes, 2010). Castelli et al. (2007) assessed the cross-sectional
association between CV fitness (Fitness- gram–PACER) and academic achievement
(Illinois State Achievement Test) in 259, 3rd through 5th grade students. There
was a positive association between CV fitness and total achievement score, math
score and reading score. Similarly, significant associations between fitness
scores and state-wide academic achievement tests in Texas were recently
reported by Welk (2010).

Based on previous study done by Manson
et al, 2015, four different domains of activity are customarily distinguished
in the study which are household, occupational, active travel/transport and
leisure-time (including sport) in contributions to mental health and positive
mental wellbeing. People achieving PA from family
activities, and those doing more diverse PAs, had better mental wellbeing.
Active travel was associated with better mental wellbeing and mental health
among the highly and moderately physically active, respectively. Highly active
people who engaged in leisure-based PA had better mental health. Long-standing
illness was associated with worse health scores, although mental wellbeing was
ameliorated amongst those who did domestic or occupational PA (Mason, Curl and Kearns, 2016).

Academic performance in the schools is
one of the determinants of whether the institution, the students or the
teachers have accomplished their educational aims. It is generally used to
define various factors that might influence student achievement in schools (Amasuomo,
2014). Some researchers believed that cognitive ability plays a significant
role in the expectation of academic achievement among school students (Lesson
et al., 2008).

Cognitive performance is an essential indicator of abilities
and skills from the psychological functional ranges such as perception,
attention (concentration), learning and retention, thinking and intelligence
(Newell et al., 2003); Tomporowski, 2008). In addition, cognitive performance
is a core mental ability that enables people to learn effectively. It support
the ability to read, remember, comprehend, interpret and analyse information.
It is essential for students’ academic performance because it strengthen higher
thinking for the acquisition of knowledge. When students’ cognitive skills are
strengthened, their overall learning ability will improve (Olivia, 2012).

Memory is a type of cognitive function that is involved in
learning and is often considered as the mental workspace where essential
information is retained in a very active state with a variety of other
cognitive processes (Pesce et al., 2009). It includes the processes of
encoding, storing, and manipulating this information. Memory enables a student
to retain information for a short time when they are using or processing it
(Baddeley et al., 1999). Inability to retain information long enough or to
handle it correctly impacts learning ability. Therefore, efficient memory is
generally considered essential for students to cope with scholastic and daily
life demnads (Olivia, 2010).

Memory is central to cognitive improvement as it is
considered to be connected to age-related increase in storage capability and
better use of available storage capacity (Pesce et al., 2009). Research has
documented that difficulty in working memory may cause learning problems which
consequently lead to poor academic performance. Moreover, students who lack
working memory and function of memory storage will face problems in learning,
which consequently lead to behavioural complications (Passolunghi & Siegel,
2001; Aronen et al., 2005). Besides, students learn by processing information,
filtering out the unintended information, and store only the intended
information into short-term memory. The information will then be encoded and
stored inlong term memory. When the information is retrieved from the long term
memory, it will again be stored into the short-term memory (Gazzaniga &
Heatherton, 2003).

Theoretical models of working memory often decsribe a role
for attention in selecting the information to be encoded into working memory
(Miyake & Shah, 1999). Fougnie (2008) recommended that attention is
important for the encoding and manipulation of information in memory. Mack
& Rock (1998) proposed that one ite should be primarily attended before it
will be encoded into memory. After encoding the information into working
memory, they will be stored there until the information is retrieved. A growing
number of studies provide strong evidences for the relationship between
attention, learning and memory. Therefore, separating attention in learning
leads to decrease prefrontal brain regions activity that is associated with
memory and it has long been recognized to reduce performance of memory (Sarter
et al., 2009).

The common indicator of obesity is body mass index (BMI). Previous
study shown the relative strengths of BMI and waist circumference as predictors
of cardio-metabolic risk in young adults from different ethno-cultural
backgrounds (Wang et al., 2005). It has been recommended that BMI, adjusted for
age and gender, is a practical estimation for overweight in adolescent and
children (National Institute for Health and Clinical Excellence & National
Collaborating Centre for Primary Care, 2006). BMI classification for children
and adolescents is presented in table 1.1.

Donnelly and colleagues completed a
3-year cluster randomized, controlled trial of 24 elementary schools among
grade 2 and 3 students to compare changes in fitness and fatness with changes
in academic achievement in schools that received PAAC. PAAC promoted 90min/week
of moderate to vigorous physically active academic lessons (3.0 to 6.0 METS,
~10 min each) delivered intermittently throughout the school day. The result
from that study was change in BMI from baseline to 3 years was significantly
influenced by exposure to PAAC. Schools with greater than 75 min of PAAC/week
showed significantly less increase in BMI at 3 years compared to schools with
lower than 75 min of PAAC/ week (Donnelly
& Lambourne 2011).

Taras and Potts-Datema (2005) reviewed
7 studies (4 cross-sectional–3 non-randomized prospective) on the association
of BMI and academic achievement. Results indicated higher BMI was associated with
lower academic achievement. Children who exceeded CDC sex and age specific BMI
standards scored lower for math, reading, and language tests compared to
students with desirable BMI status even after controlling for parent education.
On balance, Gunstad et al. (2008) found no relation between BMI and cognitive
test performance in a sample of 478 children and adolescents. Achievement
scores were significantly lower in overweight compared with non- overweight