tra_backend/diet_template/views/project_task_view.xml

<odoo>

    <record id="view_project_task_form_inherit" model="ir.ui.view">
        <field name="name">view.project.task.inherited</field>
        <field name="model">project.task</field>
        <field name="inherit_id" ref="project.view_task_form2"/>
        <field name="arch" type="xml">
            <xpath expr="//notebook/page[@name='description_page']"
                   position="before">
                <page string="Diet Plan"
                      attrs="{'invisible':[('task_type','=','workout')]}">
                    <field name="diet_plan_ids"/>
                </page>
            </xpath>
        </field>
    </record>

</odoo>