Boldenone undecylenate is a very versatile drug, and can be combined with a number of other agents depending on the desired result. For mass, it is commonly stacked with an injectable testosterone such as enanthate or cypionate. This should produce strong gains in muscle size and strength, without the same intensity of side effects of using testosterone (at a higher dose) alone. During a cutting phase, muscle hardness and density can be greatly improved when combining boldenone undecylenate with a non-aromatizable steroid such as trenbolone acetate or methenolone enanthate. Oral c-17 alpha alkylated agents such as fluoxymesterone or stanozolol may also be used, but will present some level of hepatotoxicity. For some, even the low buildup of estrogen associated with this compound is enough to relegate its use to bulking cycles only.
With Boldenon in moderate doses aromatisation is usually not a problem to worry about. But it does aromatise a little so if you are sensitive or uses Boldenon in high doses there is still a reason to look out. This means that the risk of side effects like gynocomastia and water retention is small. The small aromatisation that does occur is positive for the glucose utilization (bringing back glycogen in the cell after a hard workout) and increases your natural growth hormone release. The main advantage is that oestrogen upgrades the androgen receptors giving an anabolic effect. Boldenon is not so toxic for the liver and the DHT conversion is also low. Acne and high blood pressure problems are also rare, this steroid is in all fairly safe to use and very much recommended.