Increase label index in symfony2 form from the controller

I'm looking for a way to get label index to show it with every field from sonata_type_collection: Actually I used this code in the configureFormFields function of my admin class:

 ->add('TrainingGoals', 'sonata_type_collection', array(
                    'by_reference' => false,
                    'btn_add' => false,
                    'required' => false,
                    'label' => true,
                    'type_options' => array('delete' => false),
                    'cascade_validation' => true,
                        ), array(
                    'edit' => 'inline',
                    'inline' => 'table',
                ))

And I use this function to render only five instance of the goals form:

public function getNewInstance() {
        $object = parent::getNewInstance();

        for ($i = 0; $i < 5; $i++) {

            $trainingGoals = new TrainingGoals();
            $trainingGoals->setGoal('');
            $trainingGoals->setTraining();
            $object->addTrainingGoal($trainingGoals);
        }
        return $object;
    }

But I get only one label for all rendred fields, does this make any sense ? How can I render label like this :

 Goals 1:
 Goals 2:
 Goals 3: 
 ...

Finaly I got the solution: First I created a new type under MyBundle/Form/Type wish extend the sonata_type_collection I created this class:

    namespace AAA\AABundle\Form\Type;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilder;

class CustomSonataTypeCollectionType extends AbstractType
{

    public function getParent()
    {
        return 'sonata_type_collection';
    }
    public function getName() {
        return 'custom_field';
    }

}

Then I declared it as a service :

  mybundle.TrainingBundle.form.type.CustomSonataTypeCollection:
        class: AAA\TrainingBundle\Form\Type\CustomSonataTypeCollectionType
        tags:
            - { name: form.type, alias: custom_field }

After i added this method to my Admin class :

 public function getFormTheme() {
        return array_merge(
                parent::getFormTheme(), array('AAATrainingBundle:Form:custom_field_edit.html.twig')
        );

Finaly I created a Form folder under the View and puted my custom Form there:

{% block sonata_admin_orm_one_to_many_widget %}
    {% if sonata_admin.name == 'TrainingGoals' %}

        {% set associationAdmin = sonata_admin.field_description.associationadmin %}

        <div>
            {% for nested_group_field in form.children %}
                <ul class="nav nav-tabs">
                    {% for name, form_group in associationAdmin.formgroups %}
                        {{ associationAdmin.trans('goal', {}, 'AAATrainingBundle') }}  {{ loop.parent.loop.index }}

                    {% endfor %}
                </ul>

                <div class="tab-content">
                    {% for name, form_group in associationAdmin.formgroups %}
                        <div class="tab-pane {% if loop.first %}active{% endif %}" id="{{ associationAdmin.uniqid }}_{{ loop.parent.loop.index }}_{{ loop.index }}">
                            <fieldset>
                                <div class="sonata-ba-collapsed-fields">
                                    {% for field_name in form_group.fields %}
                                        {% set nested_field = nested_group_field.children[field_name] %}
                                        {% if associationAdmin.formfielddescriptions[field_name] is defined %}
                                            {{ form_row(nested_field, {
                                                            'inline': 'natural',
                                                            'edit'  : 'inline'
                                                        }) }}
                                            {% set dummy = nested_group_field.setrendered %}
                                        {% else %}
                                            {{ form_row(nested_field) }}
                                        {% endif %}
                                    {% endfor %}
                                </div>
                            </fieldset>
                        </div>
                    {% endfor %}
                </div>

                {% if nested_group_field['_delete'] is defined %}
                    {{ form_row(nested_group_field['_delete']) }}
                {% endif %}
            {% endfor %}
        </div>



    {%  else %}
        {% include 'SonataDoctrineORMAdminBundle:CRUD:edit_orm_one_to_many.html.twig' %}
    {% endif %}
{% endblock %}
        }