Studies has shown that both aerobic exercises and stretching exercises are equally as effective to help alleviate premenstrual symptoms.
Exercise helps to reduce and alter stress level, which in turn reduces sympathetic activity, thereby leading to reduction in menstrual pain and other premenstrual symptoms. (1,2) Also, exercise stimulates the increase in several neurotransmitters that includes natural endorphins (our natural painkillers), estrogen, dopamine and endogenous opiate (3) which aids in distracting intrusive thoughts and helps promote positive thoughts; improving moods and behaviours while reducing depression.(4)
Studies done by Sabaei et al. has shown that PMS causes a significant increase in leptin in women experiencing PMS as compared to those without. High levels of leptin circulating in women is responsible for controlling emotional behaviour and is associated with psychological symptoms of PMS. More so, many studies has shown that blood leptin levels has effectively been reduced by 30-34% through exercise and thus helps in reduction of behavioural symptoms of PMS. (5)
Regular practice of yoga has positive effects on the menstrual cycle and psychobiological well-being. Practicing yoga reduces the stress on negative effects to the immune system by balancing positively the adjustment of immunoglobulin A, thereby reducing harmful inflammatory secretions, hence making women with PMS comfortable. (6)
These yoga movements done in the studies includes breathing exercises, meditation/relaxation and different yogic postures namely cat-cow, cobra, child's pose and planks.
Strength Training - Most Optimal During Follicular Phase
High estrogen levels is attributed to increase in muscle strength and endurance where it is known that maximal concentration in estrogen and low progesterone levels happens during the follicular phase. (7) Muscle strength and fatigue rate has a remarkable difference during bleed phase in the present study, though the results are controversial.
However, the difference in muscular strength, endurance, ability to regulate temperature of the body, blood flow and metabolism have been associated with the hormonal balance throughout the phases of menstrual cycle. (8) These variance in performance are affected due to oscillations in concentrations of ovarian hormones. Levels of estrogens peaks during follicular phase, stimulating glucose availability and return glucose into type 1 muscles fibers - acting as fuel during short duration exercise. This action is inhibited by progesterone, which is dominant in luteal phase. (9)
In conclusion, it is most optimal to schedule your weight training during the follicular phase of your menstrual cycle for better performance, while focusing on aerobic and stretching exercises during the late luteal phase to help manage PMS better. Even so, every body is different. Some days your body will allow you to go a little harder in your workouts, but some days it might just be too fatigue to push any further to what you expect. Therefore it is best to listen to your body and recognise the symptoms it gives and adjust your workout intensity accordingly.
Remember, your workout is to complement your lifestyle and health, not the other way round.