diff --git a/include/Core/SPK_Group.h b/include/Core/SPK_Group.h
index 823562e..5a6335c 100644
--- a/include/Core/SPK_Group.h
+++ b/include/Core/SPK_Group.h
@@ -91,14 +91,14 @@ namespace SPK
 
 		bool isEnabled(Param param) const;
 
-		size_t getNbParticles() const;
-		size_t getCapacity() const;
+		inline unsigned int getNbParticles() const;
+		inline unsigned int getCapacity() const;
 
 		Particle getParticle(size_t index);
 		const Particle getParticle(size_t index) const;
 
-		void reallocate(size_t capacity);
-		void empty();
+		void reallocate(unsigned int capacity);
+		inline void empty();
 
 		void addEmitter(const Ref<Emitter>& emitter);
 		void removeEmitter(const Ref<Emitter>& emitter);
@@ -401,8 +401,8 @@ namespace SPK
 		{
 			bool initialized;
 
-			size_t nbParticles;
-			size_t maxParticles;
+			unsigned int nbParticles;
+			unsigned int maxParticles;
 
 			// Particles attributes
 			Vector3D* positions;
@@ -734,12 +734,12 @@ namespace SPK
 		return particleData.parameters[param] != NULL;
 	}
 
-	inline size_t Group::getNbParticles() const
+	inline unsigned int Group::getNbParticles() const
 	{
 		return particleData.nbParticles;
 	}
 
-	inline size_t Group::getCapacity() const
+	inline unsigned int Group::getCapacity() const
 	{
 		return particleData.maxParticles;
 	}
diff --git a/src/Core/SPK_Group.cpp b/src/Core/SPK_Group.cpp
index ed241df..4a7cae9 100644
--- a/src/Core/SPK_Group.cpp
+++ b/src/Core/SPK_Group.cpp
@@ -54,7 +54,7 @@ namespace SPK
 		deathAction(),
 		octree(NULL)
 	{
-		reallocate(capacity);
+		reallocate(static_cast<unsigned int>(capacity));
 	}
 
 	Group::Group(const Group& group) :
@@ -270,7 +270,7 @@ namespace SPK
 		}
 	}
 
-	void Group::reallocate(size_t capacity)
+	void Group::reallocate(unsigned int capacity)
 	{
 		SPK_ASSERT(capacity != 0,"Group::reallocate(size_t) - Group capacity must not be 0");