Mobile Ad Hoc Networks (MANETs) are wireless networks where (user) nodes act themselves as relays to other nodes, resulting in a variable topology that follows the users mobility pattern. The latter can vary from one context to another resulting in different network performance, in terms of throughput for instance. This is the rationale behind the present work where we, first, quantify the performance of the network under different mobility patterns and routing protocols, and where we, second, propose the use of fixed relays so as to enhance the performance in case of ill-behaved mobility schemes.