Asthenospermia means slow sperm motility...a risk factor for infertility. If this happened to you, you could try zinc sulphate 220 mg (50 mg elemental zinc) 2 tablets daily after food for 3 month which helped infertile men by increasing semen volume, progressive sperm motility, total normal sperm count, catalase-like activity in spermatozoa and seminal plasma, without any side effects.
I would also add other "energy producing" (and antioxidant) nutrients for the sperm including CoQ10 200 mg/d, magnesium 200-300 mg/d, carnitine 1000 mg (have your TMAO checked) and ribose 5 grams 3 x day for several months.
“Oral Zinc Supplementation Restores Superoxide Radical Scavengers to Normal Levels in Spermatozoa of Iraqi Asthenospermic Patients” International Journal for Vitamin and Nutrition Research (2015), 85, pp. 165-173. 51263
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