High-Load Resistance Training in the First Trimester, a Retrospective Survey: Implications for Exercise Professionals and Obstetrical Providers.

Abstract

This study aimed to examine whether individuals engaging in high-load resistance training (RT) make any exercise modifications during the first trimester of pregnancy, and describe pelvic floor health, fertility history, and obstetrical characteristics. Individuals <20 wk gestation who regularly engaged in RT during the first trimester were recruited and completed surveys related to preconception and first trimester pelvic health, fertility, menstrual health, relative energy deficiency in sport, and exercise behaviors. Training logs from 3 months preconception, until 12 wk of gestation were obtained from a subset of individuals. Three hundred fifty-nine participants, mean age 32.3 yr (±3.6 yr), completed surveys. From preconception to the first trimester, the frequency of training decreased (4.8 d ± 1.0 d prepregnancy vs 4.0 ± 1.3 d in first trimester, t = 11.45, P < 0.01). Most individuals continued Olympic weightlifting ( n = 127/159, 80%) and core exercises ( n = 214/234, 92%), with over half increasing or maintaining the load of RT ( n = 126/203, 62%). Fatigue and nausea reportedly impacted exercise behavior in 77% of participants. Rates of previous miscarriage were similar to those of the general population. Only 15% of participants were given counseling on exercise after miscarriage (10/68 participants). Ten individuals (3%) reported a miscarriage during enrollment in the current study. Pelvic floor complaints during exercise reduced significantly from preconception to trimester one, irrespective of whether training load was reduced or maintained. Forty-one athletes provided preconception and pregnancy training logs. In this subset of athletes, their working load was maintained from preconception across the first trimester at >75% of estimated one-repetition maximums. Continued participation of RT in the first trimester was well tolerated by those participating in RT preconception.