Undulating-cluster deadlift sets on metabolic fatigue response

Abstract Acute fatigue limits resistance training performance. A proposal of an undulating series is suggested for accumulating volume, developing strength and endurance, while improving tolerance to metabolic stress. This study compared the effects of two deadlift training configurations—cluster and undulating series—on neuromuscular and metabolic fatigue. Ten young men performed both protocols in sessions spaced 7 days apart, lifting at 75% of their one-repetition maximum (1RM). Blood lactate levels were measured before and after each protocol, while mean propulsive velocity (MPV), peak velocity (PV), and power output (PO) were measured after each repetition. Cluster series exhibited lower loss of velocity and power, demonstrating superior fatigue management. In contrast, undulating series produced greater lactate accumulation and velocity loss in longer sets, but also showed strong recovery capacity after rest periods. These findings suggest that while cluster training supports consistent performance and fatigue control, undulating series promote greater metabolic and neuromuscular stress, which may be beneficial for hypertrophy or metabolic conditioning.