CHAPTER 13: SCHool-BASEd YogA PRogRAMS • 301The issues well illustrated by the Haden et al. (2014) study show what is lost in our
understanding of the more nuanced picture of yoga outcomes when studies are aggre-
gated. Notably, when Ferreira-Vorkapic et al. (2015) looked at individual study effects they
found positive and a significant effect sizes for mood indicators, tension, and anxiety in the
POMS scale, self-esteem, and memory when the yoga groups were compared to control.
Ferreira-Vorkapic et al. (2015) noted that future research requires greater standardization
and suitability of yoga interventions for children.
In 2016, Khalsa and Butzer published their review of 47 studies with a total sample size of
4,522 participants (one study was not included due to insufficient data). Their review of the
research included research conducted in 19 elementary and preschools, six middle schools,
seven middle and high schools, and 13 high schools. The sample sizes ranged substan-
tially from a study of 20 participants to a study of 660. The review included 25 randomized
controlled trials, seven nonrandomized controlled trials, nine uncontrolled trials, and four
qualitative studies (Khalsa & Butzer, 2016). They were conducted primarily in the United
States (n = 30) and India (n = 15). The majority of studies (n = 41) were conducted from 2010
onward (Khalsa & Butzer, 2016). Most of the studies (85%) were conducted within the school
curriculum. Further, most (62%) were implemented as formal school-based yoga programs
(Khalsa & Butzer, 2016). The authors described the field as an infant research field with
most of the published research trials preliminary in nature, with numerous study design
limitations, including limited sample sizes and relatively weak research designs (Khalsa &
Butzer, 2016).
Specific positive student self-report outcomes included mood state, self-esteem, self-
control, decreased aggression and social problems, self-regulation, emotion regulation, feel-
ings of happiness and relaxation, social and physical well-being, and decreased rumination,
emotional arousal, intrusive thoughts, and alcohol use (Khalsa & Butzer, 2016). Teacher-rated
outcomes included positive findings associated with classroom behaviors, emotion skills,
independence, attention skills, transition skills, self-regulation, concentration, mood, ability
to function under pressure, attention, adaptive skills, and social skills. Teacher ratings also
indicated reductions in performance impairment, hyperactivity, behavioral symptoms,
internalizing symptoms, and maladaptive behaviors (Khalsa & Butzer, 2016). Objective data
collected from school records and academic tests showed positive intervention improve-
ments in student grades and academic performance (Khalsa & Butzer, 2016). Last, physi-
ological and cognitive outcome measures showed decreased cortisol concentrations, more stable
breathing patterns, improvement in micronutrient absorption, improved strength (i.e., grip
and abdominal), improved flexibility, improved heart rate variability, and improved stress
reactivity as indicated by skin conductance response (Khalsa & Butzer, 2016). Researchers
observed that many positive outcomes were trends (p < 0.1) rather than statistically sig-
nificant (p < 0.05). Ultimately, Khalsa and Butzer (2016) concluded that these publications
suggest that yoga in the school setting is a viable and potentially efficacious strategy for
improving child and adolescent health and therefore worthy of continued research.
When we take all of the research together, we have a good sense of all the work that is
yet to be done. Yes, this line of research is in its infancy. It faces the challenge of conduct-
ing a rigorous study within the complex system of the school district. As a researcher, I
am frequently approached by school personnel to conduct studies. However, once I begin
talking about what is required for a solid design, the IRB, pre- and posttests, and informed
consent, the enthusiasm quickly wanes. I have also experienced and observed the process of
a study slowly falling apart as roadblocks are experienced. Despite these challenges, I know