/**
 * Utility functions for calculating estimated one-rep max (1RM)
 * based on weight and repetitions performed.
 *
 * Implements four common formulas:
 * 1. Brzycki: Weight × (36 / (37 - reps))
 * 2. Epley: Weight × (1 + (0.0333 × reps))
 * 3. Lombardi: Weight × (reps ^ 0.1)
 * 4. O'Conner: Weight × (1 + (0.025 × reps))
 *
 * Note: These formulas are generally less accurate beyond 10-15 repetitions
 */
export declare enum OneRepMaxFormula {
    BRZYCKI = "brzycki",
    EPLEY = "epley",
    LOMBARDI = "lombardi",
    OCONNER = "oconner"
}
/**
 * Calculates estimated one-rep max using the Brzycki formula
 * Weight × (36 / (37 - reps))
 */
export declare function brzyckiFormula(weight: number, reps: number): number;
/**
 * Calculates estimated one-rep max using the Epley formula
 * Weight × (1 + (0.0333 × reps))
 */
export declare function epleyFormula(weight: number, reps: number): number;
/**
 * Calculates estimated one-rep max using the Lombardi formula
 * Weight × (reps ^ 0.1)
 */
export declare function lombardiFormula(weight: number, reps: number): number;
/**
 * Calculates estimated one-rep max using the O'Conner formula
 * Weight × (1 + (0.025 × reps))
 */
export declare function oconnerFormula(weight: number, reps: number): number;
/**
 * Calculates the estimated one-rep max (1RM) using the specified formula.
 *
 * @param weight - The weight lifted in kg
 * @param reps - The number of repetitions performed
 * @param formula - The formula to use for calculation (default: Brzycki)
 * @param maxAllowedReps - Maximum number of reps to consider valid (default: 15)
 * @returns The calculated one-rep max or null if inputs are invalid
 */
export declare function calculateEstimated1RM(weight: number, reps: number, formula?: OneRepMaxFormula, maxAllowedReps?: number): number | null;