Refresh $scope and list of items slow connections - angularjs

Question

I am creating a mobile app in angularjs . I call a resource that calls an API to give me values. Everything works fine , but with slow connections or 3G $ scope not cool me and therefore when browsing the list of items is old
SERVICES.JS
.factory('Exercises', function($resource) {
// localhost: Local
// 79.148.230.240: server
return $resource('http://79.148.230.240:3000/wodapp/users/:idUser/exercises/:idExercise', {
idUser: '55357c898aa778b657adafb4',
idExercise: '#_id'
}, {
update: {
method: 'PUT'
}
});
});
CONTROLLERS
.controller('ExerciseController', function($q, $scope, $state, Exercises) {
// reload exercises every time when we enter in the controller
Exercises.query(function(data) {
$scope.exercises = data;
});
// refresh the list of exercises
$scope.doRefresh = function() {
// reload exercises
Exercises.query().$promise.then(function(data) {
$scope.exercises = data;
}, function(error) {
console.log('error');
});
// control refresh element
$scope.$broadcast('scroll.refreshComplete');
$scope.$apply();
}
// create a new execersie template
$scope.newExercise = function() {
$state.go('newExercise');
};
// delete a exercise
$scope.deleteExercise = function(i) {
// we access to the element using index param
var exerciseDelete = $scope.exercises[i];
// delete exercise calling Rest API and later remove to the scope
exerciseDelete.$delete(function() {
$scope.exercises.splice(i, 1);
});
};
})
APP.js
angular.module('wodapp', ['ionic', 'ngResource', 'wodapp.controllers','wodapp.services'])
// Run
.run(function($ionicPlatform) {
$ionicPlatform.ready(function() {
// ionic is loaded
});
})
// Config
.config(function($stateProvider, $urlRouterProvider, $ionicConfigProvider) {
$stateProvider
.state('slide', {
url: '/',
templateUrl: 'templates/slides.html',
controller: 'SlideController'
})
.state('login', {
url: '/login',
templateUrl: 'templates/login.html',
controller: 'LoginController'
})
.state('dashboard', {
url: '/dashboard',
templateUrl: 'templates/dashboard.html',
controller: 'DashboardController'
})
.state('exercise', {
url: '/exercise',
templateUrl: 'templates/exercises.html',
controller: 'ExerciseController'
})
.state('newExercise',{
url: '/newExercise',
templateUrl: 'templates/newExercise.html',
controller: 'NewExerciseController'
});
$urlRouterProvider.otherwise('/');
});